Retractor

ABSTRACT

A retractor for use in surgical operations comprises a pair of blade assemblies. In operation, the blade assemblies are initially in a closed position to assume a low profile, inserted into a relatively small incision, and stretched apart from each other, thereby stretching the skin about the incision to form an aperture longer than the incision. The retractor is adapted to rotate a first blade about a first axis and a second blade about a second axis. The retractor is adapted to move the pair of blade assemblies apart along a third axis. The retractor is adapted to pivot the first blade about a fourth axis and the second blade about a fifth axis. In some embodiments, a method of performing an operation, e.g. a spinal operation, on a patient using the disclosed retractor is provided.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority benefit to U.S. Provisional PatentApplication No. 62/306,010, filed Mar. 9, 2016, which is herebyincorporated by reference herein in its entirety. This application isrelated to PCT/US2015/049211, filed Sep. 9, 2015 and U.S. ProvisionalPatent Application No. 62/048,639, filed Sep. 10, 2014, the disclosuresof each are incorporated by reference herein in their entireties.

FIELD

The present application relates to surgical methods and tools, and moreparticularly to a retractor and a method of operating a retractor.

BACKGROUND

Retractors are surgical devices used to spread bodily tissues in orderto allow a surgeon or surgical assistant to see and access a part of thebody that is to be surgically treated. In general, retractors comprise apair of jaws or blades that grip the bodily tissue and push it apartunder the force generated by an actuator, such as a pair of scissor-likearms having a distal end and a proximal end. The proximal end generallydefines a pair of handles and the distal end attaches to the pair ofblades so that manipulation of the handles causes the blades to moveapart from one another. Once an incision is made in the body to beoperated on, the blades are inserted into the incision and the actuatoris manipulated to move the blades of the retractor apart, thus spreadingthe tissue and providing an aperture through which the surgeon canaccess visualize the tissue to be surgically treated. One problem withthis type of retractor is that the aperture size is generally limited bythe size of the incision, meaning that a large aperture requires arelatively large incision. The drawback to this arrangement is thatlarger incisions result in the need for longer periods for healing ofthe incision. There is thus a need for a surgical retractor that iscapable of creating a relatively large aperture using a relatively smallincision, thereby reducing the invasiveness of the surgical procedure,post-operative healing times and patient discomfort.

INCORPORATION BY REFERENCE

All publications and patent applications mentioned in this specificationare herein incorporated by reference to the same extent as if eachindividual publication or patent application was specifically andindividually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects and advantages of the describedembodiments are described with reference to drawings of certainpreferred embodiments, which are intended to illustrate, but not tolimit. It is to be understood that the attached drawings are for thepurpose of illustrating concepts of the described embodiments and maynot be to scale.

FIG. 1 provides a perspective view of an embodiment of a retractor withthe blades in a closed position.

FIG. 2 provides a perspective view of the retractor of FIG. 1 with theblades in a closed position.

FIG. 3 provides a top view of a retractor of FIG. 1 with the blades in aclosed position.

FIG. 4 provides a perspective view of an embodiment of the retractor ofFIG. 1, with the blades in an opened position. Opening the retractoralong this axis stretches the incision along its length.

FIG. 5 provides a top view of a retractor of FIG. 4 with the blades inan opened position.

FIG. 6 provides a perspective view of the retractor of FIG. 4 in therotated position. Opening the retractor along these axes stretches theincision along its width.

FIG. 7 provides a top view of the retractor of FIG. 6 in the rotatedposition.

FIG. 8 provides a perspective view of the retractor of FIG. 6 in thepivoted position. Opening the retractor along these axes stretches theincision along its width and/or length.

FIG. 9 provides a top view of the retractor of FIG. 8 in the pivotedposition.

FIG. 10 provides a top view of the retractor of FIG. 1.

FIG. 11 provides a proximal view of the retractor of FIG. 10.

FIG. 12 provides a perspective view of a rotation mechanism of FIG. 1.

FIG. 13 provides a perspective view of a rotation mechanism of FIG. 11.

FIG. 14 provides an exploded view of a rotation mechanism of FIG. 1.

FIG. 15 provides a perspective view a pivot mechanism of FIG. 1.

FIG. 16 provides an exploded view of a pivot mechanism of FIG. 14.

FIG. 17 provides a perspective view of a slide mechanism of FIG. 1.

FIG. 18 provides an exploded view of a slide mechanism of FIG. 17.

FIG. 19 provides an exploded view of a quick release mechanism of FIG.1.

FIG. 20 provides a perspective view of an attachment mechanism of FIG.1.

FIGS. 21A-E show the use of a probe system to insert the retractor ofFIG. 1 to form an operative channel through the tissue of a patient toaccess a portion of the patient's spine.

DETAILED DESCRIPTION

As will be explained below, certain retractor embodiments describedherein provide advantages over the prior art retractors comprising a setof blades and an actuator, such as a set of scissor arms. For example,the retractor of the illustrated embodiment allows a person to insert arelatively compact set of retractor blades into an incision having ashort length. In some embodiments, the compact set of retractor blades(e.g., a first blade, a second blade, a third blade) are of such a sizethat they can be inserted within the incision so that they are snuglyembraced by the side walls of the incision (e.g., a closed position).

Optionally, an actuator causes the first blade and the second blade tomove apart (e.g., to an opened position) in a direction that can beessentially parallel to the length of the incision. This can cause thetissue to stretch in one direction (e.g., along the length of theincision), creating an opening having a length in that direction that issubstantially longer than the incision. Once the retractor is opened inthe first direction, the actuator may be locked open. Optionally, arotation mechanism on the first and/or second blades may be manipulatedto rotate the blades (e.g., to a rotated position), for example, pullingthe incised tissue apart in one or more directions that are not parallelto the incision. Optionally, a pivot mechanism on the first and/orsecond blades can be manipulated to pivot the blades (e.g., to a pivotedposition), pulling the incised tissue apart in one or more directionsthat are not parallel to the incision. Optionally, an adjuster on thefirst and/or second arms can be manipulated to slide or otherwisetranslate the arms (e.g., to a slid position), pulling the incisedtissue apart in directions that are not parallel to the incision.Optionally, an adjuster on the third blade can be manipulated to slideor otherwise translate the third blade (e.g., to a slid position),pulling the incised tissue apart in directions that are not parallel tothe incision. In some embodiments, these directions may beperpendicular, substantially perpendicular or oblique to the incision.In certain embodiments, the retractor can be used to open up an aperturethat is substantially longer and/or wider than the incision, and issubstantially larger than would be possible using a prior art deviceand/or in a manner that is easier to use and/or requiring less stepsand/or less complicated steps. In certain arrangements in relativeterms, the surgeon can use a smaller incision, and in some cases a muchsmaller incision, than would have been required with a prior art device.Moreover, in certain arrangements, removal of the retractor, e.g. byclosing the blades, closing the arms and removing the blades from theincision, can allow the incision to relax back to a size that is muchsmaller than would have resulted from use of the prior art retractor. Inaddition, in certain arrangements, steps performed by the surgeon toretract the tissue can be simplified, easier to use and/or involve lesssteps as compared to prior art devices.

The illustrated embodiment will now be further described with referenceto the appended drawings. In FIG. 1 there is shown a perspective view ofa retractor 10 having a body 26. The retractor 10 comprises a first arm12 to which can be coupled a first blade assembly 16 comprising a firstblade 18. The first blade assembly 16 can include a first rotationmechanism 20 to rotate the first blade 18. The first blade assembly 16and the first arm 12 can also include a first pivot mechanism 22 topivot the first blade 18. The first arm 12 has a proximal end 24opposite the first blade assembly 16.

The retractor 10 can include a second arm 32 to which can be coupled asecond blade assembly 36 comprising a second blade 38. The second bladeassembly 36 can include a second rotation mechanism 40 to rotate thesecond blade 38. The second blade assembly 36 and the second arm 32 caninclude a second pivot mechanism 42 to pivot the second blade 38. Thesecond arm 32 has a proximal end 44 opposite the second blade assembly36. The first arm 12 and the second arm 32 can be coupled to a slidemechanism 28 to slide the first arm 12 and the second arm 32 relative tothe body 26. The first arm 12 and the second arm 32 can be coupled to aspread mechanism 34 to slide the first arm 12 and the second arm 32relative to the body 26.

In the illustrated embodiment of FIG. 2, the retractor can include athird blade 46 coupled to the third arm 50. The third blade 46 caninclude a longitudinally extending slot 48 sized to accept a probesystem 500, described herein. In the illustrated embodiment, the probesystem 500 can be configured to be inserted from the tip of the thirdblade 46 toward the body 26. Other configurations are contemplated. Thethird arm 50 of the third blade 46 can be coupled with the slidemechanism 30 of the body 26 to slide the third blade 46 in relation tothe body 26. In the illustrated embodiment, the third blade 46 isconfigured to be inserted from underneath the body 26. The third arm 50can interlock to securely couple the third blade 46 to the body 26. Insome embodiments, the third arm 50 forms a snap fit. In someembodiments, the third arm 50 makes an audible noise when the thirdblade 46 is coupled to the body 26. Other configurations for couplingthese two components together are contemplated, such as, for example amale/female connection and/or permanently connecting the parts and/orforming the parts out of more or less components.

The first rotation mechanism 20 rotates the first blade 18 about a firstaxis 52. The second rotation mechanism 40 rotates the second blade 38about a second axis 54. In the illustrated arrangement, the first axis52 passes vertically or substantially vertically through the first blade18, and the second axis passes vertically or substantially verticallythrough second blade 38. In some embodiments, the first and second axes52, 54 may be substantially coplanar with one another. Indeed in someembodiments, the first and second axes 52, 54 are not only coplanar butalso substantially parallel to one another. In particular embodiments,the first and second axes 52, 54 are coplanar with, parallel to, or atsome pre-determined skew angle with respect to one another. As will bedescribed above, various embodiments will be described as“substantially” vertically, parallel, coplanar and/or perpendicular. Insuch embodiments, “substantially” can mean within plus or minus 25degrees from the given orientation, in other embodiments, within plus orminus 10 degrees from the given orientation, and in other embodiments,within plus or minus 5 degrees from the given orientation.

In the illustrated embodiment, the first blade assembly 16 and thesecond blade assembly 36 can translate along a third axis 56 (see e.g.,FIG. 3), e.g., spread. The first arm 12 and the second arm 32 can becoupled to a spread mechanism 34 to spread the first arm 12 and thesecond arm 32 relative to the body 26. In the illustrated embodiment,the first blade assembly 16 and the second blade assembly 36 can moverelative to one another along an arc. In the illustrated embodiment,their general direction of motion relative to one another, and thedirection of motion can be along the common third axis 56 that isgenerally defined by a line passing through the first axis 52 and thesecond axis 54. In other embodiments, the first blade assembly 16 andthe second blade assembly 36 can rotate about different axes (e.g., axesthat are parallel to each other or slightly skewed). In some examples,the third axis 56 is perpendicular or substantially perpendicular to thefirst axis 52, the second axis 54 or both the first and second axes 52,54. In particular embodiments, the third axis 56 is substantiallyperpendicular or perpendicular to both the first axis 52 and the secondaxis 54. In some embodiments, the third axis 56 is substantiallyperpendicular or perpendicular to the first axis 52, the second axis 54or both the first and second axes 52, 54. In some embodiments, the thirdaxis 56 is perpendicular or substantially perpendicular to both thefirst and second axes 52, 54. In some embodiments, the retractor 10described herein possesses a mechanism (e.g., set screw, set pin, clamp,detent, ratchet mechanism etc.) for locking the first blade assembly 16and the second blade assembly 36 in at least one predetermined positionalong the third axis 56.

The first pivot mechanism 22 can pivot the first blade 18 about a fourthaxis 58. The second pivot mechanism 42 can pivot the second blade 38about a fifth axis 60. In some such embodiments, the fourth axis 58 andthe fifth axis 60 may be substantially coplanar or coplanar with oneanother. Indeed in some embodiments, the fourth axis 58 and the fifthaxis 60 are not only coplanar but also substantially parallel orparallel to one another. In particular embodiments, the fourth axis 58and the fifth axis 60 are substantially coplanar with, coplanar with,substantially parallel to, parallel to, or at some pre-determined skewangle with respect to one another.

In the illustrated embodiment, the first blade assembly 16 and thesecond blade assembly 36 can slide along a sixth axis 62 (see e.g., FIG.3). In the illustrated embodiment, the third blade 46 can slide alongthe sixth axis 62. In some embodiments, the third blade 46 can slideindependently of the first blade assembly 16 and the second bladeassembly 36. In the illustrated embodiment, the first blade assembly 16and the second blade assembly 36 can move together in a proximal-distaldirection. In other embodiments, the first blade assembly 16 and thesecond blade assembly 36 can slide about different axes (e.g., axes thatare parallel to each other or slightly skewed). In some examples, thesixth axis 62 is perpendicular or substantially perpendicular to thefirst axis 52, the second axis 54, or the third axis 56. In particularembodiments, the sixth axis 62 is substantially perpendicular orperpendicular to both the first axis 52 and the second axis 54. In someembodiments, the sixth axis 62 is substantially parallel or parallel tothe fourth axis 58, the fifth axis 60 or both the fourth and fifth axes58, 60. In some embodiments, the retractor 10 described herein possessesa mechanism (e.g., set screw, set pin, clamp, detent, ratchet mechanismetc.) for locking the first blade assembly 16 and the second bladeassembly 36 in at least one predetermined position along the sixth axis62. In some embodiments, the retractor 10 described herein possesses amechanism (e.g., set screw, set pin, clamp, detent, ratchet mechanismetc.) for locking the third blade 46 in at least one predeterminedposition along the sixth axis 62. In some embodiments, through all theadditional movements about the axes 52, 54, 56, 58, 60, 62 the thirdblade 46 can remain stationary and fixed relative to the body 26. Inother words, during all movement of the first blade 18 and the secondblade 38 the third blade 26 can remain immobile. In some embodiments,the third blade 46 can move relative to the first blade assembly 16 andthe second blade assembly 36 through all the additional movements of thefirst blade assembly 16 and the second blade assembly 36 about the axes52, 54, 56, 58, 60, 62. For example, the third blade 46 can move alongthe sixth axis 62 while the first blade 18 and the second blade 38remain stationary. In another example, the third blade 46 can pivotrelative to the first blade 18 and the second blade 38. The third blade46 can be hingedly connected to the body 26 and can pivot toward theproximal direction to help create an enlarged aperture in the incisedtissue.

The blades 18, 38, 46 may have a variety of configurations. In someembodiments, at least one blade is substantially flat. In someembodiments (e.g., the illustrated embodiment of FIGS. 1-3), at leastone blade is bent or beveled in order to enhance the ability of theblades to lie flat when the blades are in the closed position. Thisarrangement can allow the first and second blades 18, 38 to exert forceon the skin about an incision in opposing directions substantiallyperpendicular to the blade axes and perpendicular or oblique to a corddefined by the points at which the blade axes intersect the arms 12, 32of the retractor 10. In some embodiments, one or more blades 18, 38, 46can be fan shaped.

In some embodiments, two of the blades are of substantially differentsizes in at least one dimension. In some embodiments, the at least twoblades of different sizes are the first blade 18 and second blade 38. Insome embodiments, the at least two blades of different sizes are thefirst blade 18 and the third blade 46. In some embodiments, the at leasttwo blades of different sizes are the second blade 38 and the thirdblade 46. In some embodiments, at least one of the blades 18, 38, 46 isa comb-shaped blade. In some embodiments, at least one of the blades 18,38, 46 is a substantially flat blade. In some embodiments, the retractor10 can include at least one removable blade. In some embodiments, thefirst blade 18 and the second blade 38 are removable. In someembodiments, the first blade assembly 16 and the second blade assembly36 are removable. In some embodiments, the third blade 46 is removable.The first blade 18 can include a first bridge 95 and the second blade 38can include a second bridge 96. The blades 18, 38 can have a variety oflengths of bridges 95, 96. The bridges 95, 96 can allow the blade 18, 38to be smaller than the length of the retractor 10.

The blade assemblies 16, 36 can be removed from the arms 12, 32. In somearrangement, it can be convenient to remove the blade assemblies 16, 36in order to expedite sterilization of the blade assemblies 16, 36 and/orin order to exchange one or both blade assemblies 16, 36 for other bladeassemblies (e.g. blade assemblies with different size blades, differentconfiguration of blades, etc.) as discussed in more detail herein.

In FIGS. 1-3, the retractor 10 is shown in the “closed position,”meaning that the first blade 18, the second blade 38, and the thirdblade 46 are aligned and relatively close to one another so as toprovide a smaller cross-sectional area as compared to an “openedposition”. While the application uses the phrase “the closed position,”it is understood that one or more positions may be described as closed.For instance, the blades 18, 38, 46 may be aligned, substantiallyaligned, stacked, substantially stacked, close together, relativelyclose together, the first blade 18 encloses the second blade 38, thesecond blade encloses the third blade 46, the first blade 18 enclosesthe third blade 46, one or more blades 18, 38, 46 enclose the probesystem 500, or any other closed positions.

The first blade 18, the second blade 38, and the third blade 46 can besubstantially parallel or parallel in the closed position. Thelongitudinal axes of the first blade 18, the second blade 38, and thethird blade 46 can be aligned on substantially the same or the sameplane in the closed position. The length of the three blades 18, 38, 46in this configuration can be approximately equal to the length of oneblade, such as the length of the first blade 18. The first blade 18, thesecond blade 38, and the third blade 46 can have a stackedconfiguration. The first blade 18 can be in front (e.g., distal), thesecond blade 38 can be in the middle, and the third blade 46 can be inback (e.g., proximal).

The first blade 18 can have a first rail 64 that aligns one side of theblades 18, 38, 46. The first rail 64 can extend from the proximalsurface of the first blade 18 toward the body 26. The second blade 38can have a second rail 66 that can extend from both distal surface andthe proximal surface of the second blade 38. When viewed from the distalend of the retractor 10 (as shown in FIG. 1), the first rail 64 canextend on the left side of the first blade 18 and the second rail 66 canextend on the right side of the second blade 38. This configurationpermits the first blade 18 to slide relative to the second blade 38without interference of the rails 66, 68. The rails 66, 68 can have awidth equal to the width of the stacked blades 18, 38, 46.

In FIGS. 4-9, the retractor 10 is shown in an “opened position,” meaningthat the first blade 18 can be translated relative to the third blade 46or the second blade 38 can be translated relative to the third blade 46.The first blade 18 is moved apart from the second blade 38, while thethird blade 46 can remain stationary. The first blade 18, the secondblade 38, and the third blade 46 can have an overlapped configuration inthe opened position, as shown. While the application uses the phrase“the opened position,” it is understood that one or more positions maybe described as opened. For instance, the blades 18, 38 may be slightlyspaced apart, greatly spaced apart, overlapping, not overlapping,adjacent, with a gap between, without a gap between, at any spaced apartlocation along the third axis 56, wherein the total length in the openedposition is greater than the incision length L, or any other openedpositions.

The motion of the first blade 18 can be coupled to the motion of thesecond blade 38 such that actuation of a single actuator such as thespread mechanism 34 that moves both the first blade 18 and the secondblade 38 along the third axis 56. In other embodiments, each of thefirst blade 18 and the second blade 38 is separately actuated. The firstblade 18 can be in front (e.g., distal), the second blade 38 can be inthe middle, and the third blade 46 can be in back (e.g., proximal). Thelength L′ of the three blades 18, 38, 46 in this configuration isgreater than the length L of one blade, such as the length of the firstblade 18. When viewed from the distal end of the retractor 10 (shown inFIG. 4). The first blade 18 can translate a first distance to the leftof the third blade 46. The second blade 38 can translate a seconddistance to the right of the third blade 46. The first distance can beequal to the second distance, but need not be. The configuration of therails 66, 68 permits the first blade 18 to translate relative to thesecond blade 38 without interference of the rails 66, 68.

FIG. 5 shows the top view of the retractor 10. The retractor 10 caninclude an actuator 302. The actuator 302 interacts with the arms 12, 32to spread the arms 12, 32. One embodiment of the actuator is shown inFIG. 10. Rotation of the actuator 302, in the direction of the arrow Ain FIG. 10 results in the arms 12, 32 and therefore the blade assemblies16, 36 moving apart along the directional arrows B and C, causingretractor 10 to assume the opened position depicted in FIG. 5. In theillustrated embodiment, the third axis 56 forms an arc. The first blade18 will follow an arced path away from the third blade 46. The secondblade 38 will follow an arced path away from the third blade 46. Thefirst blade 18 will follow an arced path in separating from the secondblade 38. In the illustrated embodiment, the third axis 56 can besubstantially perpendicular or perpendicular to the first axis 52 andthe second axis 54. The third axis 56 can extend perpendicularly orsubstantially perpendicularly through the first axis 52 and the secondaxis 54.

It is noted that in the embodiment depicted in FIG. 5, the retractor 10comprises a pair of arms 12 and 32 connected via a carriage 264. Otherembodiments of an actuator may be used. For example, scissor-likeactuators are known in the clamp and retractor arts. In some suchembodiments, the actuator comprises a pair of handles (not shown)coupled to the arms 12 and 32. The handles can be roughly parallel andjoined together at a pivot point. The handles can be crossed (e.g.scissor-like) handles and joined together at a pivot point. It is alsoto be understood that when the actuator is a scissor-like embodiment,the motion of blade assemblies 16 and 36 traverse an arc rather than astraight line upon opening of the retractor 10. Nevertheless, thespatial relationship of the two blade assemblies 16 and 36 can beconceptualized as changing along a line described by arrows B and C,which for the purpose of brevity is referred to herein as an axis, andin particular the third axis 56.

While the illustrated embodiment uses a mechanism for moving the firstblade 18 and the second blade 38 comprising a pair of arms 12, 32 joinedto the carriage 264, other configurations are contemplated. In someembodiments, the proximal ends 24, 44 of the arms 12, 32 can be joinedin alternative ways to the body 26 such that the movement of the arms12, 32 is not a pivoting motion. For instance, arms 12, 32 can be joinedone to another by a cross member (not shown). The cross member holds thearms 12, 32 in parallel and stabilizes the arms 12, 32. One or more arms12, 32 can be moved along the cross member in order to translate thefirst blade 18 away from the third blade 46 and to translate the secondblade 38 away from the third blade 46. In such configurations, the firstarm 12 linearly translates relative to the second arm 32 along the thirdaxis 56. In this embodiment, the third axis 56 defines a geometric linepassing through and joining the first axis 52 and the second axis 54.The first blade 18 follows a straight path away from the second blade38.

In some embodiments, the retractor 10 described herein possesses adevice for locking the first blade assembly 16 and the second bladeassembly 36 in at least one predetermined position along the third axis56. The device for locking the blade assemblies 16, 36 can be a ratchet(not shown). The device for locking the blade assemblies 16, 36 can be adetent and recess configuration. The device for locking the bladeassemblies 16, 36 can be disposed on the pivot or the cross member (notshown).

Insertion of the blades 18, 38, 46 into an incision in the closedposition (as in FIGS. 1-3) and translating the first blade 18 and thesecond blade 38 to an opened position (such as in FIGS. 4-5) results ina stretching of the incision along the third axis 56. This stretchingincreases the length of the incision from a length approximately equalto the length L of a single blade (e.g., the first blade 18) to a lengthL′ greater than the length L of a single blade (e.g., the first blade18). As can be seen in FIGS. 4-5, the retractor 10 is in the openedposition, meaning that the first blade 18 is relatively separated fromthe second blade 38 along the third axis 56. As the blade assembly 16moves along the directional arrow B and blade assembly 36 moves alongthe directional arrow C, they exert force in the direction of lines Band C, respectively.

In FIGS. 6-7, the retractor 10 is shown in the “rotated position,”meaning that the first blade 18 is rotated relative to the third blade46 and/or the second blade 38 is rotated relative to the third blade 46.While the application uses the phrase “the rotated position,” it isunderstood that one or more positions may be described as rotated. Forinstance, the first blade 18 can be rotated at any angle relative to thethird blade 46 greater than zero (e.g., 5°, 10°, 15°, 20°, 25°, 30°,35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°, 100°,105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°, 160°,165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between 30-60°,between 40-70°, between 50-80°, between 60-90°, between 70-100°, between80-110°, etc.), the second blade 38 can be rotated at any angle relativeto the third blade 46 greater than zero (e.g., 5°, 10°, 15°, 20°, 25°,30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°,100°, 105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°,160°, 165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between30-60°, between 40-70°, between 50-80°, between 60-90°, between 70-100°,between 80-110°, etc.), the first blade 18 can be rotated approximatelythe same angle as the second blade 38, the first blade 18 can be rotateda different angle as the second blade 38, wherein the width W′ in therotated position is greater than the incision width or the width of anyof the blades 18, 38, 46, or other rotated positions.

The width W′ of the three blades 18, 38, 46 in this configuration isgreater than the width W of any one blade, such as the width of thefirst blade 18 and the rail 64. The first blade 18 can rotate in aclockwise direction about the first axis 52. The second blade 38 canrotate in a counterclockwise direction about the second axis 54. Themotion of the first blade 18 can be independent of the motion of thesecond blade 38. In other embodiments, the motion of the first blade 18can be coupled to the motion of the second blade 38 such that rotationis controlled by a single rotation mechanism.

In the illustrated embodiment, the first blade 18 is rotated by a firstrotation mechanism 20 and the second blade 38 is rotated by a secondrotation mechanism 40. In some embodiments and methods of use, the firstblade 18 can rotate in an opposite direction as the second blade 38 suchthat both blades open relative to the third blade 46. The first rotationmechanism 20 can be identical, substantially similar, or a mirror imageof the second rotation mechanism 40. One embodiment of the firstrotation mechanism 20 is shown in FIG. 12-14. Other embodiments arecontemplated for rotating the first and/or second blades (e.g., variouslinkages, hinges and/or cams).

Referring to FIG. 7, turning the first rotation mechanism 20 about thefirst axis 52 in the direction of adjustment arrow D, results inrotation of the first blade 18. Turning the second rotation mechanism 40about the second axis 54 in the direction of adjustment arrow E, resultsin rotation of the second blade 38, respectively. As shown in FIG. 7,rotating the first blade 18 causes the first blade 18 to exert force inthe direction of direction arrow F, while rotating the second blade 38causes the second blade 38 to exert force in the direction of directionarrow G. In some such embodiments, the first axis 52 and second axis 54may be substantially coplanar with one another. Indeed in someembodiments, the first axis 52 and second axis 54 are not only coplanarbut also substantially parallel to one another. In particularembodiments, the first axis 52 and second axis 54 are coplanar with,parallel to, or at some pre-determined skew angle with respect to oneanother.

In the illustrated embodiment, the first blade 18 is rotated and/or thesecond blade 38 is rotated after the first blade 18 is translatedrelative to the third blade 46 and the second blade 38 is translatedrelative to the third blade 46 along the third axis 56. Thus, afterinsertion in an incision of the blades 18, 38, 46 in the closedposition, the retractor 10 is opened by the first blade 18 and thesecond blade 38 translating relative to the third blade 46 along thethird axis 56 to achieve the opened position. Then the first blade 18 isrotated relative to the third blade 46 about the first axis 52 and/orthe second blade 38 is rotated about the second axis 54 relative to thethird blade 46 to achieve the rotated position. However, this depictsonly some methods of use.

In some methods, the first blade 18 and/or the second blade 38 isrotated before the first blade 18 is translated relative to the thirdblade 46 and the second blade 38 is translated relative to the thirdblade 46 along the third axis 56. Thus, after insertion in an incisionof the blades 18, 38, 46 in the closed position, the first blade 18 isrotated about the first axis 52 relative to the third blade 46 and/orthe second blade 38 is rotated the second axis 54 relative to the thirdblade 46 to achieve the rotated position. Then the retractor 10 isopened by the first blade 18 and the second blade 38 translatingrelative to the third blade 46 along the third axis 56 to achieve theopened position. Then, if needed, the first blade 18 and/or the secondblade 38 is rotated again relative to the third blade 46 to achieve therotated position (e.g., another rotated position within the broaddefinition of the “rotated position”).

The rotated position creates and maintains an aperture in the incisedtissue that is wider W′ (i.e. dimensionally larger in a directionperpendicular or oblique to the direction of the incision) than theincision. If the first blade 18 and/or second blade 38 are rotated afterthe blades 16, 38 have been translated relative to the third blade, thenthe retractor 10 creates and maintains an aperture in the incised tissuethat is both longer L′ due to the translation (i.e. dimensionally largerin the direction of the incision,) and wider W′ due to the rotation(i.e. dimensionally larger in a direction perpendicular or oblique tothe direction of the incision) than the incision.

It is to be understood that, while this description is especially aptwhere the incision is a straight line incision of about 0.1 to about 3inches in length, it can apply to any shape of incision (e.g. an arc, asinusoid, etc.) of any length. In particular embodiments, thecontemplated size of the incision is about 0.5 to 2 inches in length andthe blades 18, 38, 46 are appropriately sized so that when the retractor10 is in the closed position the blades 18, 38, 46 fit lengthwise withinthe incision without requiring substantial stretching of the incisedtissue prior to opening of the retractor 10. Thus, in some embodiments,the blades 18, 38, 46 are sized to snugly fit within the incision whenthe retractor 10 is in the closed position.

In FIGS. 8-9, the retractor 10 is shown in the “pivoted position,”meaning that the first blade 18 is pivoted relative to the third blade46 and/or the second blade 38 is pivoted relative to the third blade 46.While the application uses the phrase “the pivoted position,” it isunderstood that one or more positions may be described as pivoted. Forinstance, the first blade 18 can be pivoted at any angle relative to thethird blade 46 greater than zero (e.g., 5°, 10°, 15°, 20°, 25°, 30°,35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°, 100°,105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°, 160°,165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between 30-60°,between 40-70°, between 50-80°, between 60-90°, between 70-100°, between80-110°, etc.), the second blade 38 can be pivoted at any angle relativeto the third blade 46 greater than zero (e.g., 5°, 10°, 15°, 20°, 25°,30°, 35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°,100°, 105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°,160°, 165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between30-60°, between 40-70°, between 50-80°, between 60-90°, between 70-100°,between 80-110°, etc.), the first blade 18 can be pivoted approximatelythe same angle as the second blade 38, the first blade 18 can be pivoteda different angle as the second blade 38, wherein the length L″ and/orthe width W″ in the pivoted position is greater than the incision lengthor width or the length or width of any of the blades 18, 38, 46, orother pivoted positions.

The width W″ of the three blades 18, 38, 46 in this configuration isgreater than the width W of any one blade, such as the width of thefirst blade 18 and the rail 64. The length L″ of the three blades 18,38, 46 in this configuration is greater than the length L of any oneblade, such as the length of the first blade 18. The first blade 18 canpivot in a clockwise direction about the fourth axis 58. The secondblade 38 can pivot in a counterclockwise direction about the fifth axis60. The motion of the first blade 18 can be independent of the motion ofthe second blade 38. In other embodiments, the motion of the first blade18 can be coupled to the motion of the second blade 38 such thatpivoting is controlled by a single pivot mechanism. The pivoted positioncreates and maintains an aperture in the incised tissue that is bothlonger L″ (i.e. dimensionally larger in the direction of the incision,)and wider W″ (i.e. dimensionally larger in a direction perpendicular oroblique to the direction of the incision) than the incision.

In the illustrated embodiment, the fourth axis 58 is perpendicular tothe first axis 52. The first blade 18 can rotate about the first axis 52and pivot about the fourth axis 58. This provides at least two degreesof freedom for the first blade 18 and allows the first blade 18 to bepositioned in a variety of locations within the incision. In theillustrated embodiment, the fifth axis 60 is perpendicular to the secondaxis 54. The second blade 38 can rotate about the second axis 54 andpivot about the fifth axis 60. This provides at least two degrees offreedom for the second blade 38 and allows the second blade 38 to bepositioned in a variety of locations within the incision. The fourthaxis 58 and the fifth axis 60 are perpendicular to the third axis 56.The movement along the third axis 56 provides an extra degree offreedom.

In the illustrated embodiment, the first blade 18 is pivoted by a firstpivot mechanism 22 and the second blade 38 is pivoted by a second pivotmechanism 42. The first blade 18 can pivot in an opposite direction asthe second blade 38 such that both blades 18, 38 open relative to thethird blade 46. The first pivot mechanism 22 can be identical,substantially similar, or a mirror image of the second pivot mechanism42. One embodiment of the first pivot mechanism 22 is shown in in FIGS.15-16. Other embodiments are contemplated for providing the describedpivoting motions such as, for example, various linkages, cams and/orhinges.

Referring to FIG. 9, pivoting the first pivot mechanism 22 about thefourth axis 58 in the direction of adjustment arrow H, results inrotation of the first blade 18. Turning the second pivot mechanism 42about the fifth axis 60 in the direction of adjustment arrow I, resultsin rotation of the second blade 38, respectively. Pivoting the firstblade 18 causes the first blade 18 to exert force in the direction ofdirection arrow J, while pivoting the second blade 38 causes the secondblade 38 to exert force in the direction of direction arrow K.

In some examples, the first axis 52 is substantially perpendicular orperpendicular to the fourth axis 58. In particular embodiments, thefirst axis 52 is at some pre-determined skew angle with respect to thefourth axis 58. In some examples, the second axis 54 is substantiallyperpendicular or perpendicular to the fifth axis 60. In particularembodiments, the second axis 54 is at some pre-determined skew anglewith respect the fifth axis 60. In some examples, the third axis 56 issubstantially perpendicular or perpendicular to the fourth axis 58, thefifth axis 60 or both the fourth axis 58 and the fifth axis 60. In someembodiments, the third axis 56 is substantially perpendicular orperpendicular to both the fourth axis 58 and the fifth axis 60. In someembodiments, the third axis 56 is perpendicular or substantiallyperpendicular to the fourth axis 58, the fifth axis 60 or both thefourth axis 58 and the fifth axis 60. In some embodiments, the thirdaxis 56 is perpendicular or substantially perpendicular to both thefourth axis 58 and the fifth axis 60.

In some embodiments, the third blade 46 can be pivoted about a seventhaxis (not shown) that is parallel to the third axis 56 and extends fromnear the connection between the third blade 46 and the body 26. In someembodiments, the third arm 50 can have a hinge that pivots the thirdblade 46. The third blade 46 can be pivoted at any angle relative to thevertical plane greater than zero (e.g., 5°, 10°, 15°, 20°, 25°, 30°,35°, 40°, 45°, 50°, 55°, 60°, 65°, 70°, 75°, 80°, 85°, 90°, 95°, 100°,105°, 110°, 115°, 120°, 125°, 130°, 135°, 140°, 145°, 150°, 155°, 160°,165°, 170°, 175°, 180°, between 10-40°, between 20-50°, between 30-60°,between 40-70°, between 50-80°, between 60-90°, between 70-100°, between80-110°, etc.). The third blade 46 can be pivoted a same angle or adifferent angle as the first blade 18 and/or second blade 38, whereinthe length L″ and/or the width W″ in the pivoted position is greaterthan the incision length or width or the length or width of any of theblades 18, 38, 46, or other pivoted positions. The seventh axis isdescribed in some embodiments as substantially parallel or parallel tothe third axis 56. In other embodiments, the seventh axis can be at somepre-determined skew angle with respect to the third axis 56.

The width W″ of the three blades 18, 38, 46 in this configuration isgreater than the width W of any one blade, such as the width of thethird blade 46. The length L″ of the three blades 18, 38, 46 in thisconfiguration is greater than the length L of any one blade, such as thelength of the third blade 46. The first blade 18 can pivot in aclockwise direction about the fourth axis 58. The second blade 38 canpivot in a counterclockwise direction about the fifth axis 60. The thirdblade 46 can pivot about the seventh axis toward the proximal direction.The motion of the third blade 46 can be independent of the motion of thefirst blade 18 and the second blade 38. In other embodiments, the motionof the third blade 46 can be coupled to the motion of the first blade 18and/or the second blade 38 such that pivoting is controlled by a singlepivot mechanism. The pivoted position creates and maintains an aperturein the incised tissue that is both longer L″ (i.e. dimensionally largerin the direction of the incision,) and wider W″ (i.e. dimensionallylarger in a direction perpendicular or oblique to the direction of theincision) than the incision.

The third blade 46 can be pivoted by a pivot mechanism that is identicalor substantially similar to the pivot mechanism described herein for thefirst blade 18 and second blade 38. Other embodiments are contemplatedfor providing the described pivoting motions such as, for example,various linkages, cams, hinges, gears and/or levers.

In the illustrated embodiment, the first blade 18 is pivoted and/or thesecond blade 38 is pivoted after the first blade 18 is rotated and/orthe second blade 38 is rotated and after the first blade 18 istranslated relative to the third blade 46 and the second blade 38 istranslated relative to the third blade 46. Thus, after insertion in anincision of the blades 18, 38, 46 in the closed position, the retractor10 is opened by the first blade 18 and the second blade 38 translatingalong the third axis 56 relative to the third blade 46 to achieve theopened position. Then the first blade 18 is rotated about the first axis52 relative to the third blade 46 and/or the second blade 38 is rotatedabout the second axis 54 relative to the third blade 46 to achieve therotated position. Then the first blade 18 is pivoted about the fourthaxis 58 relative to the third blade 46 and/or the second blade 38 ispivoted about the fifth axis 60 relative to the third blade 46 toachieve the pivoted position. In some embodiments, the third blade 46 ispivoted about the third axis 56 toward the proximal direction. However,this depicts only some methods of use.

In some methods, the first blade 18 is pivoted and/or the second blade38 is pivoted and/or the third blade 46 is pivoted before the firstblade 18 and/or the second blade 38 is rotated. In some methods, thefirst blade 18 is pivoted and/or the second blade 38 and/or the thirdblade 46 is pivoted is pivoted before the first blade 18 is translatedrelative to the third blade 46 and the second blade 38 is translatedrelative to the third blade 46.

FIGS. 10-16 show embodiments of the various mechanisms of the retractor10. FIG. 10 shows the spread mechanism 34. The spread mechanism 34 is adevice for translating the first blade 18 and the second blade 38 aboutthe third axis 56. FIG. 11 shows the proximal end of the retractor 10which includes the actuator for the spread mechanism 34. FIGS. 12-14show the rotation mechanism 40. The rotation mechanism 40 is a devicefor rotating the second blade 38 about the second axis 54. The rotationmechanism 40 can be identical, substantially similar or a mirror imageof the rotation mechanism 20 shown in FIG. 1. The rotation mechanism 20is a device for rotating the first blade 18 about the first axis 52.FIGS. 15-16 show the pivot mechanism 22. The pivot mechanism 22 is adevice for pivoting the first blade 18 about the fourth axis 58. Thepivot mechanism 42 can be identical, substantially similar or a mirrorimage of the pivot mechanism 22. The pivot mechanism 42 is a device forpivoting the second blade 38 about the fifth axis 60. Otherconfigurations are possible for rotating the blades as described hereine.g., various levers, knobs, cams, etc.

FIG. 10 shows the spread mechanism 34. The retractor 10 can include thecarriage 264. The carriage 264 can have a v-shaped configuration. Thecarriage 264 can have a first carriage arm 288 and a second carriage arm290. Each carriage arm 288, 290 can form an angle alpha, beta with alongitudinal axis 292 of the body 26. The angle alpha can be the same asthe angle beta, or the angles alpha, beta can be different. Eachcarriage arm 288, 290 can include a pin 294, 296. The pin 294 of thefirst carriage arm 288 can be connected to a slot 298 in the first arm12. The pin 296 of the second carriage arm 290 can be connected to aslot 300 in the second arm 32. The pins 294, 296 can be received withinthe slots 298, 300 allowing the arms 12, 32 to move about the pins 294,296 and allow the blade assemblies 16, 36 to translate along the thirdaxis 56.

The retractor 10 can be in the “opened position,” meaning that the firstarm 12 and the second arm 32 are displaced relative to the third blade46 along the third axis 56. While the application uses the phrase“opened position,” it is understood that one or more positions may bedescribed as open. The carriage 264 can be mounted onto a screw 304. Thescrew 304 can be located along the sixth axis 62. The screw 304 canextend in the proximal-distal direction of the body 26. The screw 304can include external threads that engage complementary internal threadson the carriage 264. The screw 304 can be configured to mate with abearing (not shown) in the carriage 264. The bearing allows the screw304 to rotate without translation (e.g., rotate in place). In someconfigurations, the carriage 264 translates along the screw 304 as thescrew 304 rotates.

The retractor 10 can include an actuator 302. The actuator 302 interactswith the arms 12, 32 to spread the arms 12, 32. In the illustratedembodiment, the actuator 302 rotates the screw 304 in the direction ofarrow A. In some embodiments, the actuator 302 can include an innerengagement 306 that abuts a proximal end of the body 26. The innerengagement 306 can include a plurality of flats designed to engage adriver. Other configurations are contemplated. In some embodiments, theactuator 302 is located within another actuator as shown in FIG. 11.

Rotation of the actuator 302 causes the carriage 264 to translate fromthe proximal end of the body 26 toward the distal end of the body 26.The carriage 264 is coupled to the pins 294, 296. As the carriage 264translates forward, the pins 294, 296 also translate forward. The slots298, 300 can be elongate channels that extend at an angle to theforward-aft direction of the movement of the pins 294, 296. The pins294, 296 can exert a force on the slots 298, 300 of the arms 12, 32 asthe pins 294, 296 move forward or aft. The angle of the slots 298, 300causes the arms 12, 32 to spread. The arms 12, 32 can pivot about theirconnection points to the carriage 264. The shape of the slots 298, 300can cause the arms 12, 32 to spread outward along the third axis 56. Oneskilled in the art will recognize that the carriage 264 can spread thearms 12, 32 in either direction.

The actuator 302 can translate the blades 18, 38 along the third axis 56irrespective of the location of the carriage 264 relative to the body26, as described herein with respect to the slide mechanism 28. Therotation mechanisms 20, 40 can rotate the blades 18, 38 irrespective ofthe location of the carriage 264 relative to the body 26. The pivotmechanisms 22, 42 can pivot the blades 18, 38 irrespective of thelocation of the carriage 264 relative to the body 26.

FIGS. 12-13 are perspective views of the second blade 38 in the closedposition and the rotated position, respectively. FIG. 14 is an explodedview of the rotation mechanism 40. Referring back to FIGS. 1, 6-7, thesefigures depict an embodiment of a second blade assembly 36, whichcomprises the second blade 38. The second blade assembly 36 comprises ahub 98. The hub 98 is coupled to the distal end of the second arm 32. Inthe illustrated embodiment, the hub 98 houses the rotation mechanism 40.Also shown in these views is the second axis 54 to achieve the rotatedposition. In some embodiments, the second blade 38 is adapted to rotateabout the second axis 54. In some embodiments, this added degree offreedom permit the second blade 38 to be rotated outward so that thesecond blade 38 is farther apart from the third blade 46. The thirdblade 46, in some embodiments, remains stationary. FIG. 6 shows aperspective view of the retractor 10 with the first blade 18 and thesecond blade 38 in a rotated position. FIG. 7 shows a top view of FIG.6.

The hub 98 can have a first connecting hole 100. The first connectinghole 100 can be non-threaded. The hub 98 is coupled to an inner barrel102. In the illustrated embodiment the inner barrel 102 is integrallyformed with the second blade 38. In other embodiments, the inner barrel102 can be coupled with the second blade 38. The second blade 38 can beconnected to the second bridge 96 which can be connected to the innerbarrel 102. The inner barrel 102 can be sized to be accepted within thefirst connecting hole 100 of the hub 98.

Referring to FIGS. 12-14, the second rotation mechanism 40 can include ascrew 104. The second rotation mechanism 40 can include a collar 106.The collar 106 can include a threaded bore 108 sized to receive thescrew 104. The screw 104 and the collar 106 are sized to be received ina lumen 110 of the inner barrel 102. The inner barrel 102 can have afirst slot 112 and a second slot 114 cut into the upper portion 116 ofthe inner barrel 102. The first slot 112 can be offset 180 degrees fromthe second slot 114. Specifically, the upper portion 116 of the innerbarrel 102 is that portion of the inner barrel 102 above the highestpoint at which the second bridge 96 connects to the inner barrel 102.The first slot 112 and second slot 114 can extend from near the top ofthe inner barrel 102 to the bottom of the inner barrel 102. The slots112, 114 extend diagonally across the upper portion 116. Although twoslots 112, 114 are shown, other configurations are contemplated (e.g.,one slot, three slots, four slots, five slots). The one or more slotsmay have the same slope and extend in the same direction.

The inner barrel 102 can have an engagement groove 118 circumscribingthe inner barrel 102 above the slots 112, 114. An appropriately sizedretention member can be received within the groove 118. The retentionmember allows the inner barrel 102 to rotate but not translate withinthe first connecting hole 100.

The lumen 110 can have an engagement groove 124 circumscribing the lumen110 above the slots 112, 114. The screw 104 can have a complementaryengagement groove 126 circumscribing the head of the screw 104. Anappropriately sized retention member 128 such as an o-ring can bereceived within the grooves 124, 126. The retention member 128 allowsthe screw 104 to rotate but not translate within the inner barrel 102.

FIGS. 12-14 further depict a first connector pin 134 and secondconnector pin 136. The number of pins equals the number of slots. Theconnector pins 134, 136 extend outward from the collar 106. In theillustrated embodiment, the first connector pin 134 is offset 180degrees from the second connector pin 136. Other configurations arecontemplated. The first connector pin 134 is sized to extend through thefirst slot 112 and the second connector pin 136 is sized to extendthrough the second slot 114.

The screw 104 fits within the threaded bore 108 of the collar 106, asdepicted in FIGS. 12-13. In this configuration, the first slot 112 formsa passage through which the first connector pin 134 fits. The secondslot 114 forms a passage through which the second connector pin 136fits. As depicted in FIG. 12, the second blade 38 can be in the closedposition when the first connector pin 134 is at the bottom of the firstslot 112 and the second connector pin 136 is at the bottom of the secondslot 114. In this configuration, as shown in FIG. 4 it is seen that thesecond blade 38, and the third blade 46 stack to form a substantiallyplanar blade set.

One skilled in the art will recognize that rotating the screw 104 cancause the collar 106 to translate up and down. The retention member 128prevents the screw 104 from translating. The connector pins 134, 136 canbe rigidly coupled to the collar 106. At least one connector pin 134 or136 can be retained in the channel 122 of the hub 98, which prevents thecollar 106 from rotating. Rotating the screw 104 will force the collar106 to rise since the screw 104 cannot translate and the collar 106cannot rotate. The connector pins 134, 136 will similarly rise with thecollar 106. As the connector pins 134, 136 rise, they act upon the slots112, 114. Due to the shape of the slots 112, 114, the inner barrel 102will rotate as the connector pins 134, 136 rise. Rotation of the innerbarrel 102 also rotates the second blade 38. In other words, rotatingthe screw 104 forces the connector pins 134, 136 to rise and act uponthe slots 112, 114, thereby causing the inner barrel 102 to rotate, andalso rotate the second blade 38 about the second axis 54. One skilled inthe art will understand that the first blade 18 can be rotated in theother direction (e.g., counterclockwise to close the first blade 18).Starting with the connector pins 134, 136 at the top of slots 112, 114,translating the collar 106 downward will force the connector pins 134,136 to move down the length of the screw 104 in the slots 112, 114,thereby causing the inner barrel 102 to rotate, thereby causing thesecond blade 38 to rotate about the second axis 54.

As can be seen in FIG. 14, the assembly of inner barrel 102, the collar106, the screw 104, and the connector pins 134, 136, fits through thefirst connecting hole 100 of the hub 98. As can be seen in FIGS. 6-7,the head of the screw 104 is visible through the hub 98 allowing thescrew 104 to be manipulated. One of skill in the art will appreciatethat the connector pins 134, 136 engage the slots 112, 114, therebypermitting the inner barrel 102 to freely turn about the second axis 54.The retention member (not shown) prevents the inner barrel 102 frommoving up or down along the second axis 54. The retention member 128 canprevent the screw 104 from moving up or down along the second axis 54.Turning the screw 104 about the second axis 54 in one direction cancause the collar 106 to move upward along the second axis 54, whileturning the screw 104 in the opposite direction can cause the collar 106to move downward along the second axis 54. As explained above, movementof the collar 106 forces movement of the connector pins 134, 136 up anddown the second axis 54. Movement of the connector pins 134, 136 in onedirection can create force in one direction on the slots 112, 114 in theinner barrel 102 causing the inner barrel 102 to rotate. The screw 104can be turned to rotate the second blade 38 toward or away from thethird blade 46. In the illustrated embodiment, the second blade 38 isconnected to a second bridge 96, which in turn is connected to the innerbarrel 102 such that rotating the inner barrel 102 about second axis 54clockwise can result in the second blade 38 also turning to clockwise.

The first blade assembly 16 can be substantially similar to theembodiment of the second blade assembly 36 described herein. Forinstance, the first blade assembly 16 can include an inner barrelsimilar to inner barrel 102, screw similar to screw 104, collar similarto collar 106, and connecting pins similar to connecting pins 134, 136.In some embodiments, the first blade assembly 16 rotates clockwise aboutthe first axis 52 away from the third blade 46 and the second bladeassembly 36 rotates counterclockwise about the second axis 54 away fromthe third blade 46. In this configuration, the inner barrel of thesecond blade assembly 36 can be a mirror image of the first bladeassembly 16. For instance, the first blade assembly 16 can have one slotwhich is the mirror image of first slot 112 and another slot which isthe mirror image of second slot 114. This slot configuration allows thefirst blade 18 to rotate clockwise, the opposite direction as the secondblade 38 described herein. The function of the connector pins of thefirst blade assembly 16 and the method of rotation can be substantiallysimilar.

FIG. 15 is a perspective view of the first blade assembly 16 in thepivoted position. FIG. 16 is an exploded view of the pivot mechanism 22.Referring back to FIGS. 8-9, these figures depict an embodiment of afirst blade assembly 16, which comprises the first blade 18. The firstblade assembly 16 comprises the hub 97. The hub 97 can be similar,identical or a mirror image of the hub 98 described with respect toFIGS. 12-14. The hubs 97, 98 can interact with the arms 12, 32 to pivotthe hubs 97, 98. The hub 97 is coupled to the first arm 12. In theillustrated embodiment, the hub 97 and the first arm 12 house the pivotmechanism 22. The arm 12 can have a second connecting hole 242 and athird connecting hole 244.

The hub 97 can include a post 246. The post 246 can be integrally formedwith the hub 97. In some embodiments, the post 246 is a separatecomponent from the hub 97 and the post 246 can be rigidly coupled to thehub 97 such that movement of the post 246 causes movement of the hub 97.The post 246 can be accepted into a bore (not shown) of the first arm12. The post 246 can have a round cross-section but other shapes arecontemplated. The post 246 can have a boss 248 extending along a portionof the length of the post 246. The boss 248 can have a substantiallysemi-circular cross-section but other shapes are contemplated. The boss248 can be rounded. The boss 248 can be integrally formed with the post246. The boss 248 can be rigidly coupled to the post 246 such thatmovement of the boss 248 causes movement of the post 246.

The post 246 can have a groove 250 circumscribing post 246. The groove250 can be toward the proximal end of the post 246 that extends into thebore. The first arm 12 can include the second connecting hole 242. Thesecond connecting hole 242 can be sized to accept a pin 252. The upperportion of the pin 252 can fit within the second connecting hole 242.The lower portion of the pin 242 can fit within the groove 250 of thepost 246. The pin 242 facilitates alignment between the boss 248 and thescrew 256, described herein. The second connecting hole 242 can benon-threaded.

The first blade 18 can be pivoted by rotating a screw 256. The secondblade 38 can be pivoted by rotating a screw 258. The screws 256, 258 canbe a hex screw. As shown in FIG. 16, the first arm 12 can include thethird connecting hole 244. The third connecting hole 244 can bethreaded. The screw 256 can be accepted into the third connecting hole244. The screw 256 can include a cutout 260. The cutout 260 can have acomplementary shape to the boss 248 extending from the post 246. Theboss 248 can be captured by the cutout 260 in the screw 256. The boss248 of the post 246 and the cutout 260 of the screw 256 can pivot thehub 97 relative to the first arm 12.

One skilled in the art will recognize that rotating the screw 256 cancause the screw 256 to translate within the third connecting hole 244.The translation of the screw 256 can exert a force on the boss 248causing the boss 248 to rotate. The translation of the screw 256 canexert a force on the post 246 causing the post 246 to rotate. The forceacting on the boss 248 and the post 246 can cause the hub 97 to pivot.As the hub 97 pivots, the pin 252 will follow the groove 250 of the post246. The pin 252 and the groove 250 maintain contact between the boss248 and the screw 256 as the screw 256 is rotated. As the screw 256 ismoved up and down, the boss 248 is moved up and down to rotate the hub97, which pivots the first blade 18. The design benefits from directdrive of the post 246 (i.e., the screw 256 positively engages androtates the post 246 in both directions) and may avoid fatigue of thepivot mechanism 22, which can occur in other designs having springs,torsion bars, or other non-direct drive configurations in one or moredirections. Fatigue can cause unintentional blade tilting.

Pivoting of the hub 97 can result in the pivoting of the inner barrel102 received in the first connecting hole 100. Pivoting the inner barrel102 can also pivot the first blade 18. In other words, rotating thescrew 256 will cause the hub 97 to pivot, thereby pivoting the innerbarrel 102 coupled to the first blade 18 and the first blade 18. Oneskilled in the art will recognize that the first blade 18 can be pivotedin either direction based on the rotation of the screw 256. Thelongitudinal axis of the post 246 can corresponds to the fourth axis 58.The longitudinal axis of the post 246 can be offset from a longitudinalaxis of the hub 97.

The second blade assembly 36 can be similar to the embodiments describedherein. For instance, the second blade assembly 36 can include a postsimilar to post 246, a pin similar to pin 252, and a screw 258 similarto screw 256. In some embodiments, the first blade assembly 16 rotatescounterclockwise about the post 246 and the second blade assembly 36rotates clockwise about a similar post when viewed from the proximal endof the retractor 10. In some configurations, the second blade assembly36 can be a mirror image of the first blade assembly 16. For instance,the screw 258 of the second assembly 36 can be threaded in the oppositedirection as the screw 256 of the first assembly 16. This configurationof the screws 256, 258 allow the second blade 38 to pivot in theopposite direction as the first blade 18 described herein. The functionof the screws, pins and the posts of the second blade assembly 36 andthe method of rotation of the screw can be similar.

FIGS. 17-18 depict an embodiment of slide mechanisms 28, 30. Theretractor 10 can be in the “slid position,” meaning that the first arm12 and the second arm 32 are displaced in the proximal-distal directionrelative to the third blade 46 along a sixth axis 62. The retractor 10can be in the “slid position,” meaning that the third blade 46 isdisplaced in the proximal-distal direction relative to the body 26 alonga sixth axis 62. While the application uses the phrase “the slidposition,” it is understood that one or more positions may be describedas slid. For instance, the first arm 12 can be slid at any positionalong the body 26, the second arm 32 can be slid at any position alongthe body 26, the third blade 46 can be slid at any position along thebody 26, the first arm 12 can be slid approximately the same distance asthe second arm 32, wherein the width in the slid position is greaterthan the incision width or the width of any of the blades 18, 38, 46, orother slid positions.

FIG. 16 depicts an embodiment of a slide mechanism 262 that provides anadditionally degree of freedom. The slide mechanism 262 can include thecarriage 264. The first arm 12 and the second arm 32 can be coupled tothe carriage 264 via pins 294, 296, as described herein. The first arm12, the second arm 32, and the carriage 264 can move as a unit relativeto the body 26.

The carriage 264 can be attached to the body 26 via a track 266. In someembodiments, the track 266 can be linear and/or parallel to the width ofthe blades 18, 38, 46. The track 266 can extend from the proximal end ofbody 26 to the distal end of the body 26, or over a portion therewithin.The track 266 can define the sixth axis 62. A screw 274 can extend alongthe track 266. The screw 274 can be configured to mate with a bearing(not shown). The bearing allows the screw 274 to rotate withouttranslation (e.g., rotate in place).

The slide mechanism 262 can include an outer cylinder 270. The outercylinder 270 can include a threaded bore 272. The threaded bore 272 cancouple with the screw 274. The outer cylinder 270 can be coupled to thecarriage 264 such that translation of the outer cylinder 270 causestranslation of the carriage 264. In some configurations, the outercylinder 270 and the carriage 264 translate along the screw 274 as thescrew 274 rotates.

The slide mechanism 262 can include an actuator 268 that permits thecarriage 264, the first arm 12, and the second arm 32 to slide along thescrew 274. The rotation of the actuator 268 can cause the outer cylinder270 to translate along the screw 274. The translation of the outercylinder 270 can cause the carriage 264, the first arm 12, and thesecond arm 32 to translate along the screw 274. The translation of theactuator 268 can cause the carriage 264, the first arm 12, and thesecond arm 32 to translate along the sixth axis 62.

Referring back to FIG. 11, the proximal end of the body 26 can includethe actuator 268. In some embodiments, the actuator 268 can include anouter engagement 276 that abuts a proximal end of the body 26. The outerengagement 276 can include a plurality of flats designed to engage adriver. Other configurations are contemplated. Rotation of the outerengagement 276 causes the carriage 264 to translate from the proximalend of the body 26 toward the distal end of the body 26 along the sixthaxis 62.

The slide mechanism 262 permits the arms 12, 32 to extend a greaterdistance from the distal end of the body 26. The slide mechanism 262permits the first blade 18 and the second blade 38 to slide relative tothe third blade 46. In the illustrated embodiment, the third blade 46 isnot coupled to the slide mechanism 262. This permits the first blade 18and the second blade 38 to slide relative to the third blade 46. Theslide mechanism 262 permits the incision to be stretched along the widthof the incision to create an opening width greater than width W″. Oneskilled in the art will recognize that the carriage 264 can translate ineither direction.

FIG. 16 also depicts an embodiment of a slide mechanism 278 thatprovides an additionally degree of freedom. The third blade 46 can becoupled to slide mechanism 278. The third blade 46 can be coupled to theslide mechanism 278 via the third arm 50. The third blade 46 and thethird arm 50 can move as a unit relative to the body 26.

The third blade 46 can be attached to the body 26 via a track 280. Insome embodiments, the track 280 can be linear and/or parallel to thewidth of the blades 18, 38, 46. The track 280 can extend from theproximal end of body 26 to the distal end of the body 26, or over aportion therewithin. A screw 286 can extend along the track 280. Thescrew 286 can be configured to mate with a bearing (not shown). Thebearing allows the screw 286 to rotate without translation (e.g., rotatein place). The track 280 can define the sixth axis 62.

The slide mechanism 278 can include an outer cylinder 282. The outercylinder 282 can include a threaded bore 284. The threaded bore 284 canmate with a screw 286. The outer cylinder 282 can be coupled to thethird arm 50. In some configurations, the outer cylinder 282, the thirdarm 50, and the third blade 46 translates along the screw 286 as thescrew 286 rotates.

The slide mechanism 278 can include an actuator 288 that permits thethird arm 50 and the third blade 46 to slide along the screw 286. Therotation of the actuator 288 can cause the outer cylinder 282 totranslate along the screw 286. The translation of the outer cylinder 282can cause the third arm 50 and the third blade 46 to translate along thescrew 286. In embodiments where the track 280 is along the sixth axis62, the translation of the outer cylinder 282 can cause the third arm 50and the third blade 46 to translate along the sixth axis 62.

Referring back to FIG. 11, the proximal end of the body 26 can includethe actuator 388. In some embodiments, the actuator 388] can include anouter engagement 390 that abuts a proximal end of the body 26. The outerengagement 390 can include a plurality of flats designed to engage adriver. Other configurations are contemplated. Rotation of the outerengagement 390 causes the third arm 50 and the third blade 46 totranslate from the proximal end of the body 26 toward the distal end ofthe body 26 along the sixth axis 62.

The slide mechanism 278 permits the third blade 46 to extend a greaterdistance from the distal end of the body 26. The slide mechanism 278permits the third blade 46 to slide relative to the first blade 18 andthe second blade 38. In the illustrated embodiment, the first blade 18and the second blade 38 are not coupled to the slide mechanism 278. Thispermits the third blade 46 to slide relative to the first blade 18 andthe second blade 38. The slide mechanism 278 permits the incision to bestretched along the width of the incision to create an opening widthgreater than width W″. One skilled in the art will recognize that thethird blade 46 can translate in either direction.

FIG. 19 illustrates a quick release mechanism 200. The first bladeassembly 16 and the second blade assembly 36 can be removed from theretractor 10. The quick release mechanism 200 can include a first tab202 associated with the first blade assembly 16 and a second tab 204associated with the second blade assembly 36. The tabs 202, 204 can belocated on the hubs 97, 98. The tabs 202, 204 can be located on the arms12, 32. The tabs 202, 204 can be depressed thereby releasing the bladeassemblies 16, 36. In some embodiments, the tabs 202, 204 can beindependently actuated.

Referring back to FIGS. 12-13, the inner barrel 102 can have anengagement groove 118 circumscribing the inner barrel 102 above theslots 112, 114. The tab 202 can have an appropriately sized retentionmember 206 such as a flange which can be received within the groove 118.The retention member 206 allows the inner barrel 102 to rotate but nottranslate within the first connecting hole 100.

The tab 202 can be biased by a spring 208. The tab 202 can be retractedtoward the body 26 to allow the inner barrel 102 to be inserted withinthe first connecting hole 100. The tab 202 can be released to engage theretention member 206 with the groove 118. The spring 208 can bias theretention member 206 toward the distal direction and into engagementwith the groove 118. The blade assemblies 16, 36 can be inserted intothe hubs 97, 98 from underneath the hubs 97, 98.

The first blade assembly 16 can include a first post 210 designed to becoupled to the first tab 202. The first post 210 can be an alignmentpost. The first post 210 can help facilitate alignment between theretention member 206 and the groove 118.

The arms 12, 32 may be removed from the body 26. For instance, in theillustrated embodiment, the pins 294, 296 can be removed to remove thearms 12, 32 from the body 26. This may occur at any time, e.g. prior toor during sterilization of the retractor 10 or during a surgicalprocedure once the retractor 10 has been opened. Removal of the body 26during surgery may afford a member of the surgical team greater freedomof motion, an improved field of view or both.

The third blade 46 may be removed from the third arm 50. For instance,in the illustrated embodiment, the third arm 50 can have a matingconfiguration such as a snap fit with the third blade 46. The thirdblade 46 may be removed at any time, e.g. prior to or duringsterilization of the retractor 10 or during a surgical procedure oncethe retractor 10 has been opened. Removal of the third blade 46 duringsurgery may afford a member of the surgical team greater freedom ofmotion, an improved field of view or both.

Some embodiments contemplate kits comprising a retractor 10. In someembodiments, the kit comprises a plurality of removable and exchangeableblade assemblies 16, 36 and/or blades 18, 38, 46. Each kit may comprisea different actuator, a different rotation mechanism, a different pivotmechanism, a different spread mechanism, and/or a different slidemechanisms. Each blade assembly may comprise a different blade. In someembodiments, the kit comprises at least three blade assemblies havingamongst the three blade assemblies at least two distinct bladeconfigurations. In other embodiments, the kit comprises from 3 to 12blade assemblies having amongst the several blade assemblies from 2 to12 distinct blade configurations. In some embodiments, the kit comprisesat least two pairs of identical, substantially similar, or mirror imageblade assemblies. In some embodiments, the kit comprises at least twopairs of mirror image blade assemblies. In other embodiments, the kitcomprises from 2 to 10, especially about 2 to 5 such pairs of bladeassemblies.

In some embodiments, the retractor 10 may be provided to a surgeon orsurgical personnel in the form of a kit comprising additional surgicalarticles and optionally instructions for the use and handling of theretractor. Such additional surgical articles may include one or more of:scalpels, suture needles, pedicle screws, suture material, spinalimplant material, spinal fusion rods, biocompatible adhesive and closurestaples.

In some embodiments, the blades 18, 38, 46 are removable. In someembodiments, the blades 18, 38, 46 may take on a variety of shapes andsizes. In some embodiments, a kit is provided comprising a plurality ofretractors having blades of various sizes, shapes or both. In someembodiments, a kit is provided comprising one or more arms and two ormore blade assemblies (optionally of varying blade sizes and/or shapes).In some embodiments, a kit is provided comprising a retractor,optionally more than two blades assemblies, at least two of which differfrom one another in size, shape or both, and one or more pedicle screwsfor performing lumbar surgery. Thus, a variety of surgical kits forperforming surgery, especially back surgery, are contemplated andmethods of using the retractor to perform surgery, especially backsurgery, are contemplated.

The retractor 10 described herein can allow the blades 18, 38, 46 topivot and swing open as described herein. The movement of the blades 18,38, 46 can cause less trauma to the tissue by gently pushing the tissueapart. The blades 18, 38, 46 can have a low profile configuration thatcan cause less trauma upon insertion. The blades 18, 38, 46 can be movedabout a variety of axes to reduce trauma. The blades 18, 38, 46 can beindependently actuated to reduce trauma.

FIG. 20 illustrates the attachment mechanism 15. The attachmentmechanism 15 can be located on the body 26. The attachment mechanism 15couples the body 26 to a fixture (not shown). The fixture can be asupport arm. The fixture can be located within the operating arena. Thefixture can support the body 26 during the procedure.

The attachment mechanism 15 can include features to enable coupling tothe fixture. The attachment mechanism 15 can be threaded. The attachmentmechanism 15 can include a serrated plate to limit rotation. Theattachment mechanism 15 can include any features to ensure a stableconnection between the fixture and the body 26.

On the market retractor systems typically have two attachment points. Afirst attachment point allows the outer blades to move relative to thefirst attachment point. A second attachment point allows another blade,for instance, a middle blade to move relative to the second attachmentpoint. With the on the market retractor systems, the retractor can losethe surgical site when changing attachment points. The retractor canshift when removed from the attachment point and switched to anotherattachment point.

FIG. 20 illustrates a single attachment point located at the attachmentmechanism 15 for the body 26. The first blade 18 and the second blade 38can move relative to the one attachment point. For instance, the firstblade 18 and the second blade 38 can pivot with the pivot mechanisms 22,42 relative to the attachment point. The first blade 18 and the secondblade 38 can rotate with the rotation mechanism 20, 40 relative to theattachment point. The first blade 18 and the second blade 38 can spreadwith the spread mechanism 34 relative to the attachment point. The firstblade 18 and the second blade 38 can slide with the slide mechanism 28relative to the attachment point.

The third blade 46 can also move relative to the one attachment point.The third blade 46 can slide with the slide mechanism 30 relative to theattachment point. The third blade 46 can pivot relative to theattachment point. Each of the blades 18, 38, 46 can move independentlyof the attachment point. Each of the blades 18, 38, 46 can moveindependently of the body 26.

The one attachment point located at the attachment mechanism 15 canprovide more stability and accuracy during retraction. The oneattachment point can maintain the position of the retractor 10 duringthe procedure. The surgeon does not need to switch between attachmentpoints to allow operation of the blades. Each blade can be manipulatedwhen the body 26 is coupled to the fixture via the attachment mechanism15. In some methods of use, the body 26 is not removed from theattachment mechanism during the course of the procedure. In some methodsof use, there is no need to find the surgical site or reposition theretractor after switching attachment points.

FIG. 21A-21E illustrates a probe system 500 and a method for its use inconjunction with the retractor 10. The probe system 500 can include oneor more probes. The probe system 500 can include one probe, two probes,three probes, four probes, etc. In FIG. 21A, the probe system 500includes an anterior probe 505 and a posterior probe 510. The probes505, 510 can form a shape having a smooth perimeter. The smoothperimeter can form a generally flat shape such as a shape having two ormore generally flat sides. In some embodiments, each probe 505, 510forms an equal half of the perimeter. In some embodiments, the posteriorprobe 510 forms greater than half of the perimeter. The anterior probe505 faces toward the front of the system (e.g., distal end when coupledto the retractor 10) and the posterior probe 510 faces toward the rearof the system (e.g., proximal end when coupled to the retractor 10).

In some embodiments, the anterior probe 505 includes an anteriorelectrode 515. In some embodiments, the posterior probe 510 includes aposterior electrode 520. The electrodes 515, 520 can be on an exteriorsurface of the probes 505, 510. The electrodes 515, 520 can be on adistal surface of the probes 505, 510. The electrodes 515, 520 can faceoutward from the probes 505, 510. The electrodes 515, 520 can bepositioned at any radial distance (e.g., 90 degrees apart, 100 degreesapart, 110 degrees apart, 120 degrees apart, 130 degrees apart, 140degrees apart, 150 degrees apart, 160 degrees apart, 170 degrees apart,180 degrees apart, etc.). In some embodiments, the electrodes 515, 520are on opposed surfaces. The anterior electrode 515 can monitor theanterior side of the probes 505, 510 and the posterior electrode 520 canmonitor the posterior side of the probes 505, 510.

The posterior probe 510 can include a mating configuration with theanterior probe 505. The mating configuration can be a tongue and grooveconfiguration. In some embodiments, the posterior probe 510 can includea groove 530 and the anterior probe 505 can include a tongue 525. Theproximal end of the posterior probe 510 can accept the anterior probe505. In some methods of use, the anterior probe 505 is aligned with theposterior probe 510. In some methods of use, the anterior probe 505 isslid down the length of the posterior probe 510 from a first end 550 ofthe posterior probe 510 toward a second end 555 of the posterior probe.In some methods of use, the anterior probe 505 is slid until theanterior electrode 515 aligns with the posterior electrode 520. Thestructure of the probes 505, 510 when coupled together can facilitateits passage through tissues of a patient (e.g., psoas muscles) which canrun parallel to the flat surfaces of the probes 505, 510. For example,the generally flat shape of the probes 505, 510 can dissect and/ordilate the tissues of a patient by separating the psoas muscle along themuscle fibers in a lateral approach to the spine. The flat surfaces ofthe probes 505, 510 can be oriented parallel to (i.e., aligned with) thelengths of the muscle fibers, which helps to minimize trauma to themuscle tissue as the probes are inserted through the psoas muscle.

The posterior probe 510 can include a retention configuration with theanterior probe 505. The retention configuration can maintain theposition of the anterior probe 505 relative to the posterior probe 505.In some embodiments, the retention configuration is a stop coupled tothe posterior probe 510. The anterior probe 505 abuts the stop therebylimiting further distal movement. In some methods of use, the anteriorprobe 505 is slid down the length of the posterior probe 510 until theanterior probe 505 abuts a stop.

The mating configuration can couple other components of the probe system500 with the probes 505, 510. The probe system 500 can include a shim535. In some embodiments, the posterior probe 510 can include the groove530 and the shim 535 can include a tongue 540. The first end 550 of theposterior probe 510 can accept the shim 535. In some methods of use, theshim 535 is aligned with the posterior probe 510. In some methods ofuse, the shim 535 is slid down the length of the posterior probe 510from the first end 550 of the posterior probe 510 toward the second end555 of the posterior probe 510. In some embodiments, the shim 535 isconfigured to couple with the third blade 46 instead of, or in additionto the posterior probe 510.

In some embodiments, the third blade 46 can include the slot 48. Theslot 48 is sized to accept one or more probes 505, 510. In someembodiments, the slot 48 is sized to accept the anterior probe 505coupled to the posterior probe 510. The slot 48 is sized to accept theshim 535. As described herein, the posterior probe 510 can form greaterthan half of the perimeter of the assembled probes 505, 510. The slot 48can limit motion of the posterior probe 510 in directions other thantranslation. The slot 48 can limit motion of the posterior probe 510after the anterior probe 505 is removed. The slot 48 can limit motion ofthe posterior probe 510 after the shim 535 is inserted.

The probes 505, 510 can be inserted underneath the third blade 46. Thethird blade 46 can be inserted underneath the third arm 50. In somemethods of use, the probes 505, 510 are aligned with the third blade 46.In some methods of use, the third blade 46 is slid down the length ofthe probes 505, 510 from the first end 550 of the probes 505, 510. Theslot 48 of the third blade 46 can fit substantially closely around theprobes 505, 510.

The retractor 10 can include a retention configuration with the shim535. The retention configuration can maintain the position of theretractor 10 relative to the shim 535. In some embodiments, theretention configuration is one or more notches 540 located on the thirdblade 46. The shim 535 includes a corresponding detent 545 that engagesone or more notches 540 thereby limiting further movement of the shim535. In some methods of use, the shim 535 is slid down the length of thethird blade 46 engaging and disengaging the one or more notches 540 onthe third blade 46. The one or more notches 540 can be in discretepositions along the third blade 46. In some embodiments, the engagementbetween the detent 545 and the notches 540 provides feedback such as anaudible click or tactile feedback for the user. Other retentionconfigurations are also contemplated, such as ratcheting hooks,releasable clamps, and the like.

In some embodiments, the shim 535 is shorter than one or more probes505, 510. In some methods of use, the shim 535 retains the retractor 10at the anchorable location instead of the probes 505, 510. The shorterlength of the shim 535 as compared to the probes 505, 510 can provideclearance around the retractor 10 for the user to work. In some methodsof use, the shim 535 is held by the third blade 46 during use.

Each probe 505, 510 can have a probe body extending between the firstend 550 and the second end 555. The second end 555 can include a tip 565for insertion within the anchorable location. In some embodiments, thesecond end 555 can include a distal shoulder 570. The distal shoulder570 can limit penetration of the probe 505, 510. In modifiedembodiments, the probe 505, 510 can have a distal end of a differentshape. For example, the probe 505, 510 can be formed without theshoulder 570 and/or without the tip 565 and/or one of both elements canbe modified in shape.

In some embodiments, probe 505, 510 coupled together can be rectangularin horizontal cross section (i.e., the plane bisecting the probe 505,510 perpendicular to the axis formed by the first end 550 and the secondend 555). In other embodiments, the probe 505, 510 coupled together canbe circular in horizontal cross section or oval in horizontal crosssection. Some representative cross sectional shape the probes 505, 510coupled together can include: a circle; an oval; a triangle; a flattenedoval; a thin flattened oval; a rounded rectangle; a thin rounded; arectangle; and a thin rectangle. Each probe 505, 510 can form a portionof the cross section, for instance half of the cross section. In yetother embodiments, the probe 505, 510 can be any other appropriateshape, including but not limited to square, triangular, and ellipsoid. Arectangular cross-sectional shape can include a shape in which thecorners of the device are rounded and/or arrangements in which theadjacent sides are not exactly perpendicular (e.g., plus or minus 10degrees, 5 degrees, 1 degrees or 0.1 degrees from perpendicular) and/orwhen the sides of the probe have ridges, bends that deviate 10%, 5%, 1%or 0.1% from the width or length of a side. FIG. 21A-21D illustrate theprobes 505, 510 which together form an oval cross section.

In some embodiments, the probes 505, 510 can be constructed out of abiocompatible metal, such as but not limited to stainless steel,titanium, and cobalt chrome moly. In other embodiments, the probes 505,510 can be constructed out of a biocompatible ceramic. In still otherembodiments, the probes 505, 510 can be constructed out of any stiff,biocompatible material, including such classes of materials as metals,ceramics, and polymers, or any combinations thereof. In someembodiments, the probes 505, 510 can be constructed out ofnon-biocompatible material and coated with a biocompatible material.

In some embodiments, the probes 505, 510 can have a vertical dimension(i.e., between ends 550, 555) in the range of about 5-50 cm, about 6-40cm, about 7-30 cm, about 7-20 cm and about 8-10 cm or any other rangewhich is appropriate to allow the probes 505, 510 to function asdesired. In some embodiments, the probes 505, 510 can have a width inits largest, non-vertical dimension, in the range of about 5 mm-5 cm,about 6 mm-4 cm, about 7 mm-3 cm, and about 8 mm-2 cm, including about1.5 cm.

In some embodiments, the shoulders 570 can extend horizontally in fromthe edges of the probes 505, 510 in the range of about 0.1-5 mm, about0.2-4 mm, about 0.3-3 mm, about 0.4-2 mm, about 0.5-1 mm, and about0.6-0.8 mm. In some embodiments, the external corners where theshoulders 570 meet the vertical edges of the probes 505, 510 can besquared. In other embodiments, the external corners where the shoulders570 meet the vertical edges of the probes 505, 510 can be rounded orsmoothed. In some embodiments, the shoulder 570 can be machined flat onthe bottom (particularly in such embodiments in which the probe 400 is ashape other than rectangular). In other embodiments, the shoulder 570can be sharpened across their entire length to form a blade along theirentire length. In other embodiments, the shoulders 570 can be aresharpened across only a portion of their length to form a blade alongonly a portion of their length. For example, in some embodiments, onlyhalf of each shoulder 570 is sharpened (e.g., either the half of theshoulders 570 abutting the tip 565 or the half of the shoulders 570abutting the edges of the probes 505, 510).

In some embodiments, the tip 565 can extend downward from the probes505, 510. In some embodiments, the tip 565 can be substantiallytriangular. In other embodiments, the tip 565 can be substantiallyparabolic. In other embodiments, the tip 565 can be a small cylindricalmember, such as a trocar. In yet other embodiments, the tip 565 can beany shape which allows anchoring of the probes 505, 510 in tissue. Insome embodiments, the edges of the tip 565 can be machined to besubstantially smooth. In other embodiments, the edges of the anchor tip565 can be sharpened to form a blade.

In some embodiments, at least a portion of the vertical edges of theprobes 505, 510 can be sharpened. In some of these embodiments, theportion of the edges of the probes 505, 510 which are sharpened can bedisposed near the second end 555 of the probes 505, 510. As arepresentative example, 1-5 cm of the edges of the probes 505, 510extending up from the second end 555 and distal shoulders 570 can besharpened to form a blade to facilitate insertion of the probes 505, 510into corporeal tissue of a patient.

The probe system 500 illustrated in FIG. 21A is a thin, blade like probehaving a flat cross-section. The flat cross-section may limit the probes505, 510 ability to be rotated within the anchorable location to detectnerve signals. In some embodiments, each probe 505, 510 includes anelectrode 515, 520 to detect nerve signals. The electrodes 515, 520 canbe positioned to detect nerve activity at locations approximately 180degrees apart. The structure of the probes 505, 510 can facilitate itspassage through tissues of a patient (e.g., psoas muscles) which can runparallel to the flat surfaces of the probe.

In operation, a physician can select a location in which he desires touse a retractor 10 to form an operative channel in the tissues of thepatient (the spine will be used in this example for illustrationpurposes only). A location is preferably selected that provides adequateaccess to an intervertebral disc space, yet minimizes the risk of injuryto the nerves extending from the intervertebral foramen. After thesurgeon selects the location for retractor 10 placement, he can make anincision in the skin and insert one or more of the probes 505, 510 byplacing the tip 565 against the surface of the patient. In some methodsof use, the probes 505, 510 are coupled prior to insertion. The surgeonapplies pressure to the first end 550 of one or more probes 505, 510.The physician can then continue to apply pressure, thereby pushing theone or more of the probes 505, 510 through the tissue of the patient,until the probes 505, 510 are fully in place. In some embodiments, animaging modality can be used during the insertion of the one or moreprobes 505, 510. As a representative, non-limiting example, X-rayfluoroscopy can be used during insertion of the one or more probes 505,510 to ensure correct placement. Any appropriate imaging modality can beused to monitor the placement of the one or more probes 505, 510. Insome embodiments, a surgeon can make an incision with anotherinstrument, such as a scalpel, prior to the insertion of the one or moreprobes 505, 510, into which the one or more probes 505, 510 is inserted.In some embodiments, a K-wire (i.e., guide wire) can first be anchoredat the location for retractor 10 placement. One or more probes 505, 510can have a passage extending through its longitudinal length to receivethe K-wire when the one or more probes 505, 510 are inserted at thesurgical location. The K-wire advantageously provides improved accuracyin placement of the one or more probes 505, 510 and can also helpstabilize the one or more probes 505, 510 during insertion through thepatient tissue.

FIG. 21B illustrates the probes 505, 510 fully in place in a patient.The probes 505, 510 have been inserted into the side of the spinalcolumn (here defined by a first vertebra 440, a second vertebra 450, andthe disc 460 between them). FIG. 21B illustrates the placement of theprobe 400 in a location in which the tip 565 can anchor the probes 505,510. As shown in FIG. 21B, the probes 505, 510 have been inserted intothe patient until the tip 565 has sunk at least some distance into thedisc 460 between the first vertebra 440 and second vertebra 450. The tip565 has sunk into the disc 460 up until the shoulders 570 of the probes505, 510. The shoulders 570 serve in this example to limit the possibleinsertion depth of the tip 565 of the probe 570.

FIG. 21C illustrates the third blade 46 of the retractor 10 (asdisclosed herein) and a placed probes 505, 510. The third blade 46 caninclude a longitudinally extending slot 48 sized to accept the probes505, 510. The third blade 46 can fit substantially closely around theprobes 505, 510. The third blade 46 can be any type of blade asdescribed above, including but not limited to a substantially flatblade. An incision I having a length L is made in a suitable tissue,such as the skin overlying or in proximity to the lumbar region of thespine.

FIG. 21D illustrates the shim 535 and the placed third blade 46 of theretractor 10 and placed probes 505, 510. The third blade 46 can includethe slot 48 sized to accept the shim 535 after the anterior probe 505 isremoved. The third blade 46 can fit substantially closely around theshim 535 and the posterior probe 510.

FIG. 21E illustrates the first blade 18 and the second blade 38 of theretractor 10 in their closed configuration placed near the third blade46. The blades 18, 38, 46 will be in their stacked configuration whencoupled. The blades 18, 38, 46 are in the closed position and alignedrelatively parallel to one another. The third arm 50 of the third blade46 can couple with the body 26. FIG. 21E shows the retractor 10 still inthe closed position.

In some methods, the retractor 10 of FIG. 21E is manipulated to achievethe opened position, as shown and described in FIGS. 4-5 and 10. In theopened position, the incision can be stretched along the length of theincision to pull open the incision. In some methods of use, translationabout the third axis 56 results in the retractor 10 opening: i.e. thefirst blade 18 and the second blade 38 move apart from one another inthe general directions of directional arrows B, C, respectively. Theincision can be stretched open in the direction of the directionalarrows B and C so that it obtains a length L′ greater than length L ofthe incision.

In some methods, the retractor 10 of FIG. 21E is manipulated to achievethe rotated position, as shown and described in FIGS. 6-7 and 12-14. Inthe rotated position, the incision can be stretched along the width ofthe incision. Turning the rotation mechanism 20, 40 in the direction ofthe arrows D and E about the first axis 52 and the second axis 54,respectively results in the rotating of the first blade 18 and thesecond blade 38 respectively, resulting in the widening of the incision.The aperture can be opened to a width W′. If the retractor is previouslyopened as shown in FIG. 4-5, then the aperture would provide an accessarea of dimensions L′ by W′ for surgical personnel to view the operatingfield, to pass instruments, sutures, implants and other surgicalmaterials through the aperture.

In some methods, the retractor 10 of FIG. 21E is manipulated to achievethe pivoted position, as shown and described in FIGS. 8-9 and 15-16. Inthe pivoted position, the incision can be stretched along the widthand/or length of the incision. Turning the pivot mechanism 22, 42 pivotsthe first blade assembly 16 and second blade assembly 36 in thedirection of the arrows H and I about the fourth axis 58 and the fifthaxis 60, respectively results in the pivoting of the first blade 18 andthe second blade 38, further stretching the incision. The aperture canbe opened to a length L″ and a width W″. The aperture can provide anaccess area of dimensions L″ by W″ for surgical personnel to view theoperating field, to pass instruments, sutures, implants and othersurgical materials through the aperture.

In some methods, the retractor 10 of FIG. 21E is manipulated to achievethe slid position, as shown and described in FIGS. 17-18. In the slidposition, the incision can be stretched along the width of the incision.Moving the slide mechanism 262 results in the translation of the arms12, 32, and therefore the translation of the blades 18, 38, causing theincision to open. Moving the slide mechanism 278 results in thetranslation of the third blade 46, causing the incision to open. Theaperture A can be opened to a width wider than width W″.

Reversal of the steps described above results in a final incision havingsubstantially the same length L and essentially no width, like theoriginal incision. By way of comparison, in order for a prior art devicehaving a pair of blades to create such an aperture, the incision wouldhave to have a length L′ or L″ and the blades would have to have a widthof W′ or W″. The present retractor 10 permits the use of a much smallerincision to create the aperture. The present retractor 10 permits lessinvasive surgical methods, quicker and more comfortable recovery fromsurgery and potentially cost savings for the medical coverage provider.

The probes 505, 510 can be removed prior to any of these steps or leftin place during the procedure. The probes 505, 510 can allow a surgeonto easily and quickly insert a retractor 10 without cutting an incisionall the way to the surgery site prior to inserting the retractor 10 intothe desired location to access the surgery site. Rather, the surgeon canquickly and easily insert the probes 505, 510 into the desired location,anchor the probes 505, 510 using the tip 565 in the desired location,slip the third blade 46 of the retractor 10 around one or more of theprobes 505, 510, and then simply slip the retractor 10 into place. Fromthis position, the first blade 18 and/or the second blade 38 can bemoved in any of the ways described herein. From this position, the firstarm 12 and the second arm 32 can be moved in any of the ways describedherein.

In some embodiments, the probes 505, 510 comprise at least one electrode515, 520, wherein the at least one electrode 515, 520 is capable ofstimulating a nerve to provoke an electromyographic response in thenerve. The probes 505, 510 can sense nerve activity as a probe andanchor the retractor 10 at an anchorable location. In some embodiments,the first end 550 of the probes 505, 510 can be broken off once thesecond end 555 of the probes 505, 510 is implanted. The probes 505, 510can have one or more break points along the length of the probes 505,510 to facilitate this break. The break points can provide clearancearound the retractor 10 for the user to work.

In some embodiments, only one electrode is used. In other embodiments, aplurality of electrodes can be used, including about 1-10 electrodes,about 2-8 electrodes, about 3-6 electrodes and about 4-5 electrodes. Insome embodiments, at least one electrode can be disposed on the tip 565.In some embodiments, at least one electrode can be disposed on theprobes 505, 510. The electrode 515, 520 can be included in any of theembodiments described herein.

In some embodiments, the probe system 500 comprises an endoscope 499,wherein the endoscope 499 can comprise an imaging element 432 at thedistal end 412 of the endoscope 499. In some of these embodiments, theendoscope 499 can be configured to both allow a surgeon to visualize theplacement of the probe system 500 as well as allow a surgeon to slide aretractor 10 down over the probe system 500 and into place as describedherein to create an operative channel. In some embodiments, theendoscope 499 can include a tip. Such an endoscope can be applied to anyof the embodiments described herein.

The method of use can include any step described herein. In some methodsof use, the probe system 500 can facilitate placement of the retractor10 relative to an anatomical feature of the patient. The probe system500 can be used on a portion of the spine including a first vertebra440, a second vertebra 450, and a disc 460 disposed between the firstvertebra 440 and the second vertebra 450, as shown in FIGS. 21A-21B.FIG. 21A illustrates the probes 505, 510 being inserted into a patient(not fully shown) toward the spine (only a first vertebra 440, secondvertebra 450, and disc 460 are illustrated in this representativeexample). In some methods of use, an incision is made on the patient. Insome methods of use, the anterior probe 505 and the posterior probe 510are inserted into a patient, preferably into an anchorable location,such as a collagenous tissue, bone, or vertebral disc. In some methodsof use, the posterior probe 510 and the anterior probe 505 are coupledwith the mating configuration prior to insertion within the patient. Theprobes 505, 510 are inserted while assembled together. In some methodsof use, the posterior probe 510 is inserted first. The anterior probe505 is slid along the length of the posterior probe 510 toward theanchorable location.

In some methods of use, one or more probes 505, 510 includes anelectrode 515, 520 to monitor the patient. In some embodiment, eachprobe 505, 510 includes an electrode 515, 520. In some methods of use,each electrode 515, 520 monitors nerve activity. In some methods of use,the electrodes 515, 520 monitor nerve activity in opposite directions.In some methods of use, the electrodes 515, 520 monitor nerve activityin directions 180 degrees apart.

In some methods of use, the probes 505, 510 are secured to the disc 460.In some methods of use, a K-wire is inserted and attached to the disc460. In some embodiments, a K-wire (i.e., guide wire) can first beanchored at the location for retractor 10 placement. One or more of theprobes 505, 510 can have a passage extending through its longitudinallength to receive the K-wire when the probes 505, 510 are inserted atthe surgical location. The K-wire advantageously provides improvedaccuracy in placement of the probes 505, 510 and can also help stabilizethe probes 505, 510 during insertion of the retractor blades through thepatient tissue.

In some methods of use, one or more blades of the retractor 10 areinserted over the probes 505, 510. In some methods of use, one or moreblades of the retractor 10 are inserted over the probes 505, 510 afterthe probes 505, 510 are secured to the anatomy. In some methods of use,the third blade 46 of the retractor 10 is slid around the probes 505,510. The third blade 46 can be slid from the first end 550 of the probes505, 510 toward the second end 555 of the probes 505, 510. In somemethods of use, the first blade 18 and the second blade 38 of theretractor 10 are placed in their closed configuration. The third blade46 can be coupled to the third arm 50 underneath the body 26. The blades18, 38, 46 will be in their stacked configuration when coupled.

In some methods of use, the anterior probe 505 is removed from theanchorable location. In some methods of use, the anterior probe 505 isremoved after the retractor 10 is inserted over the probes 505, 510. Insome methods of use, the anterior probe 505 is slid toward the first end550 of the posterior probe 510. In some methods of use, the retractor 10remains coupled to the posterior probe 510 after the anterior probe 505is removed.

In some methods, the shim 535 is inserted into the anchorable location.In some methods of use, the shim 535 is inserted after the anteriorprobe 505 is removed. In some methods of use, the shim 535 is slid alongthe length of the posterior probe 510 toward the anchorable location. Insome embodiments, the shim 535 engages the mating configuration of theposterior probe 510. In some methods of use, the shim 535 engages thethird blade 46. In some methods of use, the detent 345 of the shim 535engages one or more notches 340 of the third blade 46. In some methodsof use, the notches 340 retain the shim 535 in a desired positionrelative to the third blade 46.

In some methods of use, the posterior probe 510 is removed from theanchorable location. In some methods of use, the posterior probe 510 isremoved after the shim 535 is inserted into the anchorable location. Insome methods of use, the K-wire or other securing device is removed fromthe anchorable location. In some methods of use, the K-wire or othersecuring device is removed after the shim 535 is inserted into theanchorable location.

In some methods of use, the third blade 46 remains coupled to the shim535 during use. In some methods of use, the third blade 46 remains atthe anchorable location during use.

The shim 535 can allow a surgeon to easily and quickly insert aretractor 10 without cutting an incision all the way to the surgery siteprior to inserting the retractor 10 into the desired location to accessthe surgery site. Rather, after the third blade 46 is inserted over theprobes 505, 510, the surgeon can quickly and easily insert the shim 535onto the third blade 46 of the retractor 10 into the desired location,and then simply slip the first blade 18 and second blade 38 of theretractor 10 into place. From this position, the first blade 18 and/orthe second blade 38 can be moved in any of the ways described herein.From this position, the first arm 12 and the second arm 32 can be movedin any of the ways described herein. The probes 505, 510 can be removedprior to any of these steps or left in place during the procedure.

The probe system 500 can be more accurate than other systems inmaintaining the position of the surgical site. The probe system 500 canhave small tolerances between components of the probe system 500. Theposterior probe 510 is inserted at an anchorable location, as describedherein. The probes 505, 510 find and monitor the surgical site with oneor more electrodes 515, 520. The K-wire secures the surgical site. Theposterior probe 510 can include a lumen to accept a K-wire therethrough.The inner diameter of the lumen can closely match the outer diameter ofthe K-wire to limit movement between the K-wire and the posterior probe510. The probes 505, 510 can have a mating configuration. The matingconfiguration can limit movement between the anterior probe 505 and theposterior probe 510 in directions other than translation. Thecombination of the K-wire and one or more probes 505, 510 can maintainthe position of the surgical site.

The interaction between the slot 48 of the third blade 46 and theposterior probe 510 can maintain the position of the surgical site.There is little movement between the probes 505, 510 and the slot 48.The posterior probe 510 can be greater than half of the perimeter of theslot 48. The inner diameter of the slot 48 can closely match the outerdiameter of the posterior probe 510 to limit movement between the slot48 and the posterior probe 510 in a direction other than translation.The inner diameter of the slot 48 can closely match the outer diameterof the posterior probe 510, alone or when mated with the anterior probe505 or the shim 535.

As described herein, there is little movement between the K-wire and theprobes 505, 510. As described herein, there is little movement betweenthe posterior probe 510 and the slot 48. As described herein, there islittle movement between the probes 505, 510 and the slot 48. Asdescribed herein, there is little movement between the posterior probe510 coupled to the shim 535 and the slot 48. This limitation of movementcan limit the shifting of the retractor 10 from the surgical site.

While certain embodiments have been shown and described herein, it willbe obvious to those skilled in the art that such embodiments areprovided by way of example only. Numerous variations, changes, andsubstitutions will now occur to those skilled in the art withoutdeparting from the invention. It should be understood that variousalternatives to the embodiments described herein may be employed. It isintended that the following claims define the scope of the invention andthat methods and structures within the scope of these claims and theirequivalents be covered thereby.

Further features of this disclosure are given in the following numberedclauses:

Clause 1. A retractor comprising:

-   -   a first blade,    -   a first rotation mechanism that rotates the first blade about a        first axis,    -   a second rotation mechanism that rotates the second blade about        a second axis,    -   a first pivot mechanism that pivots the first blade about a        fourth axis, wherein the    -   fourth axis is skewed to the first axis;    -   a second pivot mechanism that pivots the second blade about a        fifth axis, wherein    -   the fifth axis is skewed to the second axis.        Clause 2. The retractor of clause 1, wherein the first and        second axes are substantially coplanar with one another.        Clause 3. The retractor of clause 2, wherein the first and        second axes are coplanar with one another.        Clause 4. The retractor of clause 1, further comprising an        actuator that translates the first blade and second blade about        a third axis.        Clause 5. The retractor of clause 4, wherein the third axis is        substantially perpendicular to the first axis, the second axis        or both the first and second axes.        Clause 6. The retractor of clause 4, wherein the third axis is        substantially perpendicular to both the first axis and the        second axis.        Clause 7. The retractor of clause 4, wherein the third axis is        perpendicular to the first axis, the second axis or both the        first and second axes.        Clause 8. The retractor of clause 4, wherein the third axis is        perpendicular to both the first and second axes.        Clause 9. The retractor of clause 4, further comprising a device        for locking the first and second blades in at least one        predetermined position along the third axis.        Clause 10. The retractor of clause 1, further comprising an        actuator that slides the first blade and second blade about a        sixth axis.        Clause 11. The retractor of clause 10, wherein the sixth axis is        substantially perpendicular to the first axis, the second axis        or both the first and second axes.        Clause 12. The retractor of clause 10, wherein the sixth axis is        substantially perpendicular to both the first axis and the        second axis.        Clause 13. The retractor of clause 10, wherein the sixth axis is        perpendicular to the first axis, the second axis or both the        first and second axes.        Clause 14. The retractor of clause 10, wherein the sixth axis is        perpendicular to both the first axis and the second axis.        Clause 15. The retractor of clause 10, wherein the sixth axis is        substantially parallel to the fourth axis, the fifth axis or        both the fourth and fifth axes.        Clause 16. The retractor of clause 10, wherein the sixth axis is        substantially parallel to both the first axis and the second        axis.        Clause 17. The retractor of clause 10, wherein the sixth axis is        parallel to the fourth axis, the fifth axis or both the fourth        and fifth axes.        Clause 18. The retractor of clause 10, wherein the sixth axis is        parallel to both the first axis and the second axis.        Clause 19. The retractor of clause 10, further comprising a        device for locking the first and second blades in at least one        predetermined position along the sixth axis.        Clause 20. The retractor of clause 1, further comprising an        actuator that translates the first blade and second blade about        a third axis and an actuator that slides the first blade and        second blade about a sixth axis.        Clause 21. The retractor of clause 20, wherein the sixth axis is        substantially perpendicular to the third axis.        Clause 22. The retractor of clause 20, wherein the sixth axis is        perpendicular to the third axis.        Clause 23. The retractor of clause 20, further comprising a        device for locking the first and second blades in at least one        predetermined position along the sixth axis.        Clause 24. The retractor of clause 1, further comprising a third        blade that remains stationary during movement of the first blade        and the second blade.        Clause 25. The retractor of clause 24, wherein the first and        third blades are of different sizes in at least one dimension.        Clause 26. The retractor of clause 24, wherein at least one of        the first, second and third blades is a flat blade.        Clause 27. The retractor of clause 1, further comprising a third        blade and a third pivot mechanism that pivots the third blade        about a seventh axis, wherein the seventh axis is skewed to the        fourth axis.        Clause 28. The retractor of clause 1, wherein at least one blade        is removable.        Clause 29. The retractor of clause 1, wherein the first and        second blades are removable.        Clause 30. A retractor blade assembly, comprising:    -   a first blade having attached thereto a first barrel, the first        barrel having a wall and defining a first lumen, a first slot in        the wall having a first slope,    -   a first screw having an axis, the first screw fitting within the        first lumen of the first barrel    -   a collar having an inner surface configured to mate with the        outer surface of the first screw, the collar having a hole that        aligns with the first slot in the wall of the first barrel;    -   a connecting pin fitting through the hole and the slot such that        movement of the collar along the axis causes the first barrel to        rotate in a first direction; and    -   a hub comprising a first connecting hole, wherein the first        barrel fits within the first connecting hole.        Clause 31. The blade assembly of clause 30, wherein the hub is        adapted to be removably affixed to an arm of a retractor.        Clause 32. The blade assembly of clause 30, wherein the hub        comprises a second connecting hole and a third connecting hole,        wherein the retractor blade assembly further comprises a second        screw configured to be received within the third connecting        hole, a pin configured to be received within the second        connecting hole, wherein movement of the second screw causes the        hub to rotate about a post.        Clause 33. A retractor blade assembly, comprising:    -   a first blade having attached thereto a first barrel,    -   a hub having a second connecting hole and a third connecting        hole,    -   a second screw configured to be received within the third        connecting hole;    -   a pin configured to be received within the second connecting        hole; and    -   a post extending into the hub, the post comprising a groove        configured to accept the pin;    -   wherein movement of the screw causes the hub to rotate about the        post.        Clause 34. The blade assembly of clause 33, wherein the hub is        adapted to be removably affixed to an arm of a retractor.        Clause 35. The blade assembly of clause 33, wherein the hub        comprises a first connecting hole, wherein the first barrel fits        within the first connecting hole, the first barrel having a wall        and defining a first lumen, a first slot in the wall having a        first slope, a first screw having an axis, the first screw        fitting within the first lumen of the first barrel, a collar        having an inner surface configured to mate with the outer        surface of the first screw, the collar having a hole that aligns        with the first slot in the wall of the first barrel, and a        connecting pin fitting through the hole and the slot such that        movement of the collar along the axis causes the first barrel to        rotate in a first direction.        Clause 36. A retractor, comprising:    -   a first arm having a distal end and a proximal end;    -   a second arm having a distal end and a proximal end;    -   a first blade coupled near the distal end of the first arm;    -   a first rotation mechanism that rotates the first blade about a        first axis;    -   a second blade coupled near the distal end of the second arm        rotatable about a second axis;    -   a second rotation mechanism that rotates the second blade about        the second axis, wherein the first axis is substantially        parallel to the second axis;    -   a first pivot mechanism in mechanical communication with the        first blade and adapted to pivot the first blade about a fourth        axis, wherein the first axis is skewed to the fourth axis; and    -   a second pivot mechanism in mechanical communication with the        second blade and adapted to pivot the second blade about a fifth        axis, wherein the second axis is skewed to the fifth axis.        Clause 37. The retractor of clause 36, further comprising a        third blade and a third pivot mechanism in mechanical        communication with the third blade and adapted to pivot the        third blade about a seventh axis, wherein the seventh axis is        skewed to the fourth axis.        Clause 38. A retractor, comprising:    -   a first arm having a distal end and a proximal end;    -   a second arm having a distal end and a proximal end, at least        the distal end of the first arm and the distal end of the second        arm being movable toward and away from each other;    -   a first blade attached near the distal end of the first arm and        a device for moving the first blade about a first axis to adopt        at least an opened position and a closed position;    -   a second blade attached near the distal end of the second arm        and a device for moving the second blade relative a second axis        different from the first axis to adopt at least an opened        position and a closed position; and    -   a device for moving at least the distal end of the first arm and        the distal end of the second arm relative to one another along a        third axis that is not parallel to the first and second axes.        Clause 39. A retractor blade assembly, comprising:    -   a first arm having a distal end and a proximal end;    -   a second arm having a distal end and a proximal end, at least        the distal end of the first arm and the distal end of the second        arm being movable toward and away from each other;    -   a first blade attached near the distal end of the first arm and        a device for pivoting the first blade about a fourth axis;    -   a second blade attached near the distal end of the second arm        and a device for pivoting the second blade relative a fifth axis        different from the fourth axis; and    -   a device for moving at least the distal end of the first arm and        the distal end of the second arm relative to one another along a        third axis that is not parallel to the fourth and fifth axes.        Clause 40. A method of using a retractor, comprising:    -   rotating a first blade of a retractor about a first axis;    -   rotating a second blade of a retractor about a second axis,        wherein the first axis is substantially parallel to the second        axis;    -   translating the first blade and the second blade about a third        axis    -   pivoting the first blade about a fourth axis, wherein the fourth        axis is skewed to the first axis; and    -   pivoting the second blade about a fifth axis, wherein the fourth        axis is skewed to the second axis.        Clause 41. A method of using a retractor, comprising:    -   making an incision in a tissue of a body;    -   providing a retractor;    -   rotating a first blade of a retractor about a first axis;    -   rotating a second blade about a second axis, wherein the first        axis is substantially parallel to the second axis;    -   pivoting the first blade about a fourth axis, wherein the fourth        axis is skewed to the first axis; and    -   pivoting the second blade about a fifth axis, wherein the fifth        axis is skewed to the second axis.        Clause 42. The method of Clause 41, further comprising        positioning the first and second blades substantially parallel        to each other to form a first closed blade assembly.        Clause 43. The method of Clause 41, further comprising        positioning a third blade substantially parallel to the first        and second blades in a closed position.        Clause 44. The method of Clause 43, further comprising pivoting        the third blade about a seventh axis, wherein the seventh axis        is skewed to the fourth axis.        Clause 45. The method of Clause 43, further comprising inserting        the first blade, the second blade, and a third blade within the        incision.        Clause 46. The method of Clause 41, further comprising actuating        the retractor such that the first blade and second blade are        moved apart from one another along a third axis and the incision        is stretched along the length of the incision to create an        opening longer than the incision.        Clause 47. The method of Clause 41, further comprising actuating        the retractor such that the first blade and second blade are        slid together along a sixth axis and the incision is stretched        along the width of the incision to create an opening wider than        the incision.        Clause 48. The method of Clause 41, further comprising creating        an aperture in the tissue that is longer and wider than the        incision.        Clause 49. A retractor comprising:    -   a first blade,    -   a first rotation mechanism that rotates the first blade about a        first axis,    -   a second blade,    -   a second rotation mechanism that rotates the second blade about        a second axis,    -   a first pivot mechanism that pivots the first blade about a        fourth axis, wherein the fourth axis is skewed to the first        axis;    -   a second pivot mechanism that pivots the second blade about a        fifth axis, wherein the fifth axis is skewed to the second axis.        Clause 50. The retractor of clause 49, further comprising an        actuator that translates the first blade and second blade about        a third axis.        Clause 51. The retractor of clause 50, wherein the third axis is        perpendicular to the first axis, the second axis or both the        first and second axes.        Clause 52. The retractor of clause 49, further comprising an        actuator that slides the first blade and second blade about a        sixth axis.        Clause 53. The retractor of clause 52, wherein the sixth axis is        perpendicular to the first axis, the second axis or both the        first and second axes.        Clause 54. The retractor of clause 49, further comprising a        third blade.        Clause 55. The retractor of clause 54, wherein at least one of        the first, second and third blades is a flat blade.        Clause 56. The retractor of clause 54, wherein at least one        blade is removable.        Clause 57. The retractor of clause 54, further comprising a        third pivot mechanism that pivots the third blade about a        seventh axis, wherein the seventh axis is skewed to the fourth        axis.        Clause 58. A method of using a retractor, comprising:    -   making an incision in a tissue of a body;    -   providing a retractor;    -   rotating a first blade of a retractor about a first axis;    -   rotating a second blade about a second axis, wherein the first        axis is substantially parallel to the second axis;    -   pivoting the first blade about a fourth axis, wherein the fourth        axis is skewed to the first axis; and    -   pivoting the second blade about a fifth axis, wherein the fifth        axis is skewed to the second axis.        Clause 59. The method of clause 58, further comprising        positioning the first and second blades substantially parallel        to each other to form a first closed blade assembly.        Clause 60. The method of clause 58, further comprising        positioning a third blade substantially parallel to the first        and second blades in a closed position.        Clause 61. The method of clause 60, further comprising pivoting        the third blade about a seventh axis, wherein the seventh axis        is skewed to the fourth axis.        Clause 62. The method of clause 60, further comprising inserting        the first blade, the second blade, and a third blade within the        incision.        Clause 63. The method of clause 58, further comprising actuating        the retractor such that the first blade and second blade are        moved apart from one another along a third axis and the incision        is stretched along the length of the incision to create an        opening longer than the incision.        Clause 64. The method of clause 58, further comprising actuating        the retractor such that the first blade and second blade are        slid together along a sixth axis and the incision is stretched        along the width of the incision to create an opening wider than        the incision.        Clause 65. The method of clause 58, further comprising creating        an aperture in the tissue that is longer and wider than the        incision.

1. A retractor comprising: a first blade coupled to a first hub, thefirst hub comprising a post and a boss, a second blade, and a firstpivot mechanism configured to pivot the first blade by rotating theboss.
 2. The retractor of claim 1, wherein the first hub furthercomprises a first rotation mechanism that rotates the first blade abouta first axis.
 3. The retractor of claim 2, wherein the first pivotmechanism is configured to pivot the first blade about a fourth axis,wherein the fourth axis is skewed to the first axis.
 4. The retractor ofclaim 2, further comprising an actuator configured to translate thefirst blade and second blade about a third axis.
 5. The retractor ofclaim 4, wherein the third axis is perpendicular to the first axis. 6.The retractor of claim 2, further comprising an actuator configured toslide the first blade and second blade about a sixth axis.
 7. Theretractor of claim 6, wherein the sixth axis is perpendicular to thefirst axis.
 8. The retractor of claim 1, further comprising a thirdblade.
 9. The retractor of claim 8, wherein at least one of the first,second, and third blades is a flat blade.
 10. The retractor of claim 8,wherein at least one blade is removable.
 11. The retractor of claim 8,wherein the first hub further comprises a first rotation mechanism thatrotates the first blade about a first axis.
 12. (canceled) 13.(canceled)
 14. A method of using a retractor, comprising: making anincision in a tissue of a body; inserting a first probe and a secondprobe into the incision; inserting a third blade of a retractor over thefirst probe and the second probe; removing the second probe; inserting ashim along the third blade of the retractor; and removing the firstprobe.
 15. (canceled)
 16. (canceled)
 17. (canceled)
 18. (canceled) 19.(canceled)
 20. (canceled)
 21. (canceled)
 22. (canceled)
 23. (canceled)24. (canceled)
 25. (canceled)
 26. The method of claim 14, whereininserting a shim along the third blade of the retractor comprisesinserting the shim within a channel of the first probe.
 27. The methodof claim 14, further comprising monitoring nerve activity with a firstelectrode of the first probe.
 28. The method of claim 27, furthercomprising monitoring nerve activity with a second electrode of thesecond probe.
 29. The method of claim 28, wherein the first electrodeand the second electrode are separated by approximately 180 degrees whenthe first probe and the second probe are inserted into the incision. 30.The method of claim 14, further comprising engaging notches of the thirdblade with the shim to position the shim in discrete locations.
 31. Themethod of claim 14, further comprising coupling a first blade, a secondblade, and the third blade to a body of a retractor.
 32. The method ofclaim 31, further comprising attaching the body of the retractor to asingle attachment point.
 33. (canceled)
 34. (canceled)
 35. (canceled)36. (canceled)
 37. (canceled)
 38. A retractor comprising: a first bladeand a second blade adjustable in an axial direction; a third bladeadjustable in the axial direction; and an attachment point, wherein thefirst blade, second blade and third blade are adjustable in the axialdirection relative to the attachment point.